


The Tale of Two Timelines

by Reader010



Category: Undertale (Video Game)
Genre: Abuse, Alternate Universe - Underfell, Alternate Universe - Underswap, Brothers, Fontcest, Honey Mustard - Freeform, M/M, Science, Sibling Incest, Slow Build, Timelines, Underfell Papyrus, Underfell Sans, Underswap Papyrus, Underswap Sans, edgeberry, honeymustard - Freeform
Language: English
Status: Completed
Published: 2016-09-09
Updated: 2017-08-05
Packaged: 2018-08-13 12:52:46
Rating: Mature
Warnings: Graphic Depictions Of Violence, Rape/Non-Con
Chapters: 11
Words: 102,044
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7977415
Author URL: https://archiveofourown.org/users/Reader010/pseuds/Reader010
Summary: <blockquote class="userstuff">
              <p>Red could feel it in his soul. The sort of cracking that felt just like every layer of bone being chipped away as the skeleton's fingers found their usual place. The same sense of hurt Boss made sure to leave him with for every weakness the skeleton had and each mistake he made. That feeling that was all because of this- because of this happiness that would never be his. Because of this life worth living that taunted him by waving itself in front of his face, knowing fully well it'd never be his.</p><p>Blue, too, could feel it. The life draining from him as he learned that everything he'd ever been sure of was a lie. The cold sense of dread that slowly crept inside as he realized that he might never see his Papy again. That he might never go home again. That this was Blue's home now, at the side of a demanding, perverted and murderous version of his brother. A monster so monstrous and full of hate that days prior, Sans hadn't believed a monster like him could exist.</p><p>This is the interwoven story of two universes; Underswap and Underfell, and the skeletons whose lives were forever changed by an unexplainable anomaly.</p><p>~THIS STORY IS DEAD~</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> Excluding this chapter and some other exceptions, the story will typically alternate between Underswap and Underfell every other chapter. Enjoy!

The rhythmic sound of a knife chopping vegetables against the wood of a cutting board echoed out of the kitchen. Each of the young skeleton's slices thinly diced the toppings for dinner. Onions, lettuce, tomatoes... All the usual ingredients for their favorite meal, laid out across the worn cutting board that lie on the kitchen counter.

In the room off from the kitchen, the skeleton's older brother lie on the couch lazily, occupied in thought yet still keeping one of his ears expertly trained on his brother's chopping, to make sure nothing went awry. Papyrus knew that the other skeleton would be fine- cooking was something Sans had a lot of practice with. The likelihood that the knife would slip or fall from the younger skeletons hands and harm him was nonexistent. Yet Papyrus still found himself listening in careful, and watching out the corner of his eye.

"You better not start without me!" Sans warned the other as continued his chopping.

"Relax," Pap chuckled from his spot on the couch. "It wouldn't be much of a movie night if I started it without you. Besides, I don't even have the remote yet."

"That doesn't mean I don't want to see the beginning of it!" The blade, covered with the last shreds of its healthy, consumable enemies, was placed down on the counter by the smaller skeleton. Quickly, Sans sprinkled the defeated veggies on top of the two plates of tacos. It was the same thing Sans always made for dinner- yet somehow it still remained the young monster's favorite. "Undyne said the beginning was the best part!"

"What?" His older brother was in disbelief. "That's ridiculous. The start of these things are always slow and boring. They're too busy setting up the story for anything actually cool to happen."

"Nuh-uh!" Sans walked out of the kitchen holding the two plates. He passed one to his brother on the couch, just as he took his usual place on the other side of the couch, where he rested his mouthwatering meal on the table.

"Pass me the remote, will you?" Papy asked, lazily reaching across the room for a remote that wasn't remotely close enough for him to grasp without getting up.

"Oh come one!" Sans complained. "You're right next to it!"

"Yeah, but if I get up to grab it, then I'll ruin the delicious meal my brother made for me," Sans couldn't hide the small suspicion that he was just saying that, but he still couldn't help but smile to himself, silently beaming at the compliment. Papy saw the happy look on his brother's face and couldn't help but smile right alongside him. "Alright, alright. I'll get it." A familiar orange glow enveloped the remote, and it slowly levitated it's way toward Pap's spot on the couch.

Wide blue eyes looked on with their usual amazement. His big bro's powers were out-of-this-world awesome. Which made it even more astounding that he was using it to complete such a simple everyday task. "Only you would use all your magic for the sole purpose of being lazy," Sans pouted, but he was more jealous than actually upset with his brother's laziness. How come he didn't get cool telepathic powers? No wait- that was wrong. Telepathic was the other one. This was what- telekinesis? Sans opened his mouth to ask the question to the other skeleton, since that was his first instinct whenever he became curious about something. And unfortunately, he came to regret asking it almost immediately.

"Telepathic powers?" Papyrus shook his head. "Nah bro, I think your getting confused with my _television_ powers," Sans groaned as the black screen flashed on with the press of the button in Papy's hand. "It's like telekinesis, but, you know, infinitely more useful."

"Start the movie before I decide this was a mistake," It was an empty threat, and both skeletons knew that. The two of them looked forward to this weekly tradition way too much to ever give it up. It was the one night of the week where Sans stayed up late with his brother, watching whatever sort of movies they could get their hands on. The one night of the week where Papy wasn't at Muffet's late or tinkering in his workshop in the back of the house until the early hours of morning.

Usually, the two of them would just watch any of the old movies they owned and had seen a hundred times. The entire thing wasn't really even about the movie, it was more just so the two skeletons could spend time together. Yet this time Sans had convinced Undyne to lend her another one of her human movies. The smaller skeleton wasn't really too sure what the movie was about. It was like a cartoon, just like all of Undyne's movies. Except it was more like... a mature cartoon. For grown-ups. Like Alphys or his brother or Undyne or even- well- him, since he was watching it too.

"I don't know Sans," Pap said between munching on bites of his taco. "This beginning is pretty boring..." He faked a snore, and his little bro jokingly shoved him with his foot.

"Shush! Undyne said a really good part comes up next!" Sans said, star shaped pupils fixated on the glowing light of the screen before him. Sure enough, the camera panned upward, facing toward the dark night sky of the surface as someone continued to talk. Yet the younger skeleton just tuned the voice out.

"Wow..." His own starry eyes widened to take in the hundress of specks of light on screen. He had seen the stars before in other human movies, but every time he saw them he couldn't help but be completely enamored by them. Even if it was just a cartoon. He could hardly imagine what the real stars must look like! There must be millions of them- far more than they could fit on their tiny television screen.

"It's really much different than the crystals down here," Papyrus agreed, him too having a hard time tearing his gaze from the screen.

And so the two of them continued, just like that. Talking to each other over the movie, not caring that they were missing what the human characters were saying or whatever it was that was going on story wise. Because both skeletons knew that movie night was just about relaxing with each other for a couple hours. And if that meant Sans had to put up with Papy's horrendous "jokes," then so be it.

After both of them finished their tacos, the smaller skeleton crawled over to the other side of the couch and his brother shifted wordlessly, already knowing what his brother was doing. Sans cuddled up next to Pap, lying in front of his brother. The larger skeleton rested his head on the arm rest, his chin laying on Sans' head. Both skeletons' feet stretched across the couch. The younger one's legs ended at his brother knees, reminding Sans of just how short he was.

The movie was over before they knew it, but the duo stayed up talking, instead switching the television to Napstaton for background noise while they chatted.

"I've been thinking about trying to make something new," Sans said, shifting around in his brother's grasp.

"Oh yeah? Like what?" Papy replied, curious. It wasn't too often that his brother strayed from routine.

"I heard of these things called chocolate tacos the other day-" He'd found an empty box in the dump, after his weekly training with Alphys. The idea had struck him as so genius, he knew he had to try it. The taste of the combination of beef, cheese, and chocolate must have been absolutely extraordinary if humans went as far as to prepackage the meal. He couldn't wait to try it for himself.

"No," Pap said, with a concrete authority that he reserved for very rare circumstances. Sans turned in his space to look at his brother. He was so close that his body was touching the orange hoodie that his brother always wore, but he was able to pull away far enough to make his normal pouting face. "That's cheating," His brother complained, yet Sans did not let up. The older skeleton sighed. "Do you not remember the last time you had chocolate?"

Sans thought for a moment. He had no idea what his brother was talking about. "...no?"

"Exactly," Pap went on to explain. "It was like the coffee incident, only _slightly_  better." Sans huffed, knowing that he had lost. His big bro was probably right- sugar and him did not mix well, if his track record was anything to go by. Defeated, Sans leaned back into the comfort Pap's chest, and for a moment, all the pair did was sit in silence, the only sound filling the room being the television.

"Hey Pap?" It was the smaller monster who broke the silence.

"Yeah?" His brother's reply was groggy and slurred, and it was evident that he was teetering on the edge of sleep.

"Do you ever think I'll see the stars?" Papyrus froze up behind him for a second, and Sans could feel his bro's rigid spine straightening, yet he didn't think anything of it. "Like the real ones," Sans looked at the ceiling wishfully, but his mind was imagining far beyond that. "Up there?" All the way up on the surface.

"...yeah," Pap said, relaxing back once more. "I think we all will."

Sans smiled, believing every word his brother said. "I can't wait."

"Yeah..." Pap smiled, but with his back to the larger skeleton, Sans couldn't see the tired expression behind the smile. "Me neither."

There was another pause, much shorter this time, before Sans opened his mouth and asked a new, equally challenging question. "What is the surface like?"

Papyrus shrugged. "How am I supposed to know?"

"I mean, what do you think it's like?"

Pap said nothing for a moment as he thought. When he answered, he talked slowly, as if he was unsure. "I imagine it's like the underground but... bigger."

"That's it?" Sans seemed disappointed. All the monsters he knew seemed so eager to go to the surface. Surely it had to be for some other reason besides it being _bigger._ The Underground seemed plenty big to Sans. All of monster kind was able to live down here. For what reason did monsters even need to go to the surface then?

"I'm working on it!" Papyrus playfully snapped, nudging Sans' shoulder gently. "I think the surface is bigger... but also not as kind."

"Huh?" Sans asked, now confused. He had grown up among monsters that were always super nice. The thought that a living being could be anything but that was foreign to him. Not just foreign- completely impossible.

"I mean... I imagine it's not that the humans are mean..." Papy doubled back. "It's just that they're less... caring." 

"Oh." Sans said, before moving closer to Papyrus. The idea couldn't really seem to stick in Sans' mind. "Yeah." Maybe his brother was wrong about that. After all, his big bro himself had said he didn't know everything. Papy had said that it was impossible for any living thing- human or monster- to know everything. That there were just too many ideas and thoughts and things for one being to ever have the capacity to learn.

Pap cleared his throat. "Now, any more hard questions for me or are you ready to go to sleep?"

Sans smiled. "I think I'm good," He cuddled closer to Papyrus, the two of them not needing a blanket when they slept like this, both skeletons able to produce enough body heat to keep each other warm.

"Goodnight Papy." He burrowed his head deeper into his brother's hoodie. The smaller skeleton breathed in, inhaling the smells of honey and smoke that was his big brother's usual aroma. Weirdly enough, the two contrasting scents seemed to compliment each other perfectly, and Sans couldn't help but find comfort in the familiarity of it.

"Goodnight Sans." The larger skeleton responded, wrapping an arm around his little brother to pull him close- either in a protective gesture, to keep the younger skeleton safe, or as natural instinct.

* * *

It took a moment for Papyrus to come back down from the rush. The usual feelings of ecstasy and orgasm had filled him only momentarily, but the last memories of his pleasure still filled his thoughts, completing overtaking his mind. In the room, only heavy panting sounded, coming from both monsters, but primarily from the smaller skeleton beneath him.

"Boss..." The sound of his pet whimpering his name brought him back, a smirk claiming his lips. He pulled out slowly, and his brother sighed beneath him, relaxing back into the comfort of the bed.

"Who said you were done?" The dark clad skeleton demanded, pulling the leash attached to his pet's collar. Sans was pulled out of the relaxing hold of the bed, forcing him to sit at an awkward angle as he attempted to get back up. 

"Clean it up." He demanded, referring to the mess the two of them had just made.

The smaller skeleton's face burned red in embarrassment. "Yes... sir." The feeling of his pet's tongue licking the sensitive areas and bones that had been stained by their latest session sent more waves of pleasure into his already fried mind.

Papyrus' eyes landed on the leash he was holding, his eyes following it down to Sans' neck. There was very little passion in these sessions of theirs. It was just something they did so the two of them could get off. And nothing quite got the tall skeleton off like the feeling of absolute power, of absolute control over his willing subject-

As his pet's tongue licked roughly over a particularly sensitive area, Papyrus could help but moan between his teeth, buckling back a bit. Alright, not _absolute_  control.

He could feel the smirk on Sans' face as he continued to clean up. Taking it upon himself to wipe the expression off his brother's face, he placed two fingers beneath Sans' chin. He lifted the skeleton's skull up with ease, forcing their eyes to meet. With his own tongue, the larger skeleton quickly overpowered the smaller one. Catching him by surprise, he forced his way into the smaller skeleton's mouth. Their red tongues danced until Sans was the one to pull away first, gasping for breath. Papyrus' fingers were still positioned on his chin. He moved the bony figures across his brother's cheek, caressing him.

"Don't forget your place," The larger skeleton warned, quickly pulling away from the other while scratching his cheekbone. What could've previously been mistaken as a gentle caress quickly turned violent, cutting into the outer bone of the smaller skeleton's skull. The motion left a faint mark across his pet's face, something that Papyrus smiled at. Nothing quite like the feeling of marking what's _yours._

"...right." Sans dejectedly replied, looking away from his brother as a quick pain seared along his cheek. A new part of the collection of things that proved Papyrus' ownership of him. _As if this damn collar wasn't already enough._

This wasn't something that was new to either of them. The two of them has been doing this to relieve stress for years. Sans wasn't really sure what his thoughts were of having to bottom, especially to his younger brother. Yet the leash and collar were a new low. They'd only done it the last few times, but now his brother insisted on him wearing the collar all the time now. The possessive freak. And if he didn't, Papyrus would take it upon himself to _punish_  Sans for his disobedience. And admittedly, those punishments were a lot less enjoyable for him than their regular sessions. His brother didn't seem to mind though. He seemed to get to same kick out a torturing him as he did fucking him. The sick fuck.

"You missed some," His boss said, snapping his leash. Sans jolted in place before looking down at his Boss' bottom half.

"I did," Sans agreed, yet he made no motion to anything about it. He may be wearing a collar and leash, but he wasn't a complete bitch. He could rebel when he wanted to.

Another tug pulled him closer to the spot. The Boss' skull was inches away from his own now. Papyrus only glared at Sans. "Clean." The smaller skeleton heard the order but did nothing.

"I like you a bit dirty," He replied, smirking at his boss. Papyrus narrowed his eyes at him. The silent test of power began between the two of them.

Surprisingly, it seemed it was Sans who won. The boss tore his glance from his brother, looking away.  "Fine... I suppose you can clean up after our session tomorrow morning." Papyrus turned back to his brother to catch his reaction.

Sans nearly choked. "So soon?" Look what his rebellious side had done for him- though that wasn't very surprising. He honestly didn't know what he had expected.

"Yes, is that a problem?" It was phrased like a question, but it clearly wasn't. He may have been rebellious, but he wasn't stupid. The underlying threat beneath the statement was very obviously there, like it was for everything Papyrus told him to do.  _O_ _r would you rather I punished you for your disobedience?_ And Sans knew from experience that Boss would follow through on those threats.

Sans gritted his teeth tight, but offered no protest. He knew better than to do something as stupid as that. "Fine."

Papyrus smirked once more. "Good," He lied back in his bed, taking up most of the room in the cum soaked bed. "Rest up, my pet. Lots of work to do tomorrow. Lots of fun to have."

Sans sighed and laid down in his designated spot beside his boss, right on the edge of the bed. The leash was still tightly curled around Papyrus' fingers, so he couldn't get back to his own room even if his brother allowed it.

He knew it was mostly his fault that he was treated like this, but he couldn't help but feel the anger and rage boiling inside of him. He could feel Papyrus' bony fingers stroking the top of his head, and he nearly exploded in anger. It felt as if he had allowed himself to be treated like a pet, like a toy, for so long that he finally became one. It was as if in his brother's eyes, Sans had stopped being his brother and instead become... whatever the hell this was.

He heard Papyrus' breathing even out beside him and he knew his brother was asleep. He would be soon to follow, their sessions always left him exhausted. He still was stuck pinned to Papyrus' side, his leash tightly gripped by his stubborn brother even in his sleep.

Sans' sighed and his red eyes glared at the ceiling above Boss' bed. All he could do was hold out hope that tomorrow would be better, but in the end, the truth was he'd been hoping for that same thing for years now. And not once had that hope ever been met with anything other than disappointment. The only thing that ever seemed to change in this hellhole was that everything seemed to get shittier with each passing day. His hope for a better future- or even just a somewhat tolerable one- was nothing more than a far fetched dream, no more grounded in reality than a fairytale. It did him good to remember that.

But sometimes it wasn't that easy. Sometimes he couldn't help but imagine a life where everything was just a little bit better. Sans supposed letting himself think like that was a bad thing... but he found that was the only thing that kept him going, through the abuse and the violence and the whole lot of it. The false idea of there being some sort of salvation at the end of it. Yet that was all it was. Something completely false. A dream constructed so flimsily that it would collapse underneath itself if Sans' mind dwelled on it too long, possibly taking Sans with it. It was a lie to himself- blatant and impossible.

But... it wasn't all bad. Sometimes it was good to take a look at the bright side, even if a majority of it was drowned out by the surrounding darkness. He was safe. Nobody dared to mess with the leader of the Royal Guard's bitch. Nobody saw him as a threat. And he'd be lying if he said he also didn't get off to the things him and his brother did. For as much of a sick pervert that his brother was, he was very much the same way. If not worse.

Instinctively he curled up closer to his boss, a shiver running down his spine. Of course the asshole had to hog all of the sheet. Wedging his way closer he was able to grab some of the sheet for himself. Ignoring the soaked spots and stains that were always growing in number on this blanket, Sans tried his best to get some sleep, knowing that in the morning he'd have to repeat it all again. Like always.

* * *

The freezing cold was probably the only reason that Sans woke up.

At first, the young skeleton groaned in protest, feeling the frozen ache chill through the bones of his body. Without the slightest bit of hesitation, the short monster twisted his body to face the back of the couch, and blindly groped about, searching for the warm mass of his brother. When Sans' gloved fingers instead made contact with the soft fabric of the sofa, blue eyes flew open.

Except for him, the couch was completely empty. Huh.

Weird.

Sans was _always_ up first. The skeleton had trained himself to always wake bright and early, so he could prepare for the day ahead of him. In fact, he was usually up so early, he had time to make breakfast, shower, and get dressed before having to wake his bro up. If he didn't wake him up, Pap would probably sleep the entirety of the day away, completely missing his guard duty. Which brought him back to the weirdness of the scenario. Papy almost never willing got up early. Usually Sans' constant struggle to pull him out of bed was accomplished with the help of the scent of breakfast downstairs.

However, Sans decided that the only way to combat the weirdness of the idea was to simply shrug it off. Whatever had stirred Pap to get up so early surely must of been of importance. Sans could just ask whenever he returned. Pushing himself off the couch, the skeleton shook the remaining sleepiness away. His exhausted state made it obvious to him that he had woken up even earlier than he usually did.

Sans started to make his way to the kitchen to prepare some breakfast- if his brother wasn't going to join him, that was fine, but the future member of the Royal Guard needed subsistence! After all, breakfast was the most important meal of the day. Yet only two steps down his path, the skeleton nearly tripped and fell over something he had not expected to be there. Quickly recovering into a stumble, Sans was able to steady himself, yet he found his gaze still falling, until it caught on the unexpected hazard that had nearly sent him sprawling to the ground.

It was... armor. Jet black in color, with shoulder pads that seemed impractically sharpened to a point. Bulky and black, the item was clearly out of place, but before Sans could even question it, something else managed to grab his attention. A red boot- no- two of them, both tossed carelessly past the armor, forming a path to the stairs. And then beyond that was another item- something dark red and tattered, caught onto the railing of the stairway.

A piece of cloth. Almost a carbon copy of the size and material of the one wrapped around Sans' neck, the only real differences being the color and condition of it. Sans wore his light blue cloth as part of his battle body- his specially crafted protective gear (made with the help of Papy) that he wore day and night, due to the fact that its comfort and style were matched only by its ability to keep him ready for action at a moment's notice- but that was beside the point.

The skeleton had never seen anyone else try to pull off the style he had long since adopted. Yet the presence of this red cloth, and the armor, and the boots, too... they could all only mean one thing, right? They were nearly mirror images of his own battle body, only in different colors. Black armor for Sans' gray, red boots and bandana for his blue. It couldn't be a coincidence. Somebody had specifically picked out the same things that Sans wore. Combine that with the fact that Papy was nowhere to be found, and that could only led to one logical conclusion.

And that one logical conclusion was that Sans' bro had decided to make his own, _super rad, one of a kind battle body_ , and the two of them would become what they had always been destined to be.  **Battle. Body. Bros.**

Obviously.

It was such a good idea that Sans could've squealed in excitement. His bro was _so_ awesome. Only he could think of an idea so absolutely, undeniably cool. Just thinking about it made Sans giddy. The two of them, out at their posts, in matching, kick-butt, color coordinated armor. Sans gasped quietly to himself. They'd be just like the superheroes in all the movies! Undyne and Alphys would definitely think this was the best thing ever- he had to tell them about it- later. Later being immediately after he got to see it for himself. 

Papy had probably snuck off early in order to get it all ready, so he could surprise Sans. But it seemed like, in his excitement, his bro had accidentally left a few pieces of the battle body downstairs. Not that Sans could blame him- the younger skeleton had difficulty containing his own excitement at the idea, and he wasn't even the one who got to make the outfit.

Sans figured he should pick the stuff up and take it to Pap's room. After all, it was the least he could do to thank his bro for doing something so awesome. Plus, Sans would be lying if he said he didn't want to see Papy's battle body right now. But... if Sans saw his bro in the outfit before it was complete, that would ruin the surprise, wouldn't it? Sans really didn't want to do that. He wanted to make sure this was special.

A growling in his stomach reminded Sans of his unsatisfied appetite. He had gotten so distracted with the idea of Papy and him getting to be Battle Body Bros, that he had forgotten about the most important meal of the day. Seeing Pap's epic new style would have to wait, unfortunately, until Sans had finished getting breakfast.

Bubbling with excitement and ready to burst, Sans continued on his path to the kitchen. His happy mood pulsed through him as he scavenged the cabinets and fridge of the room, on the search for his first meal of the day. His joyful attitude flickered only momentarily at the realization that no pancake mix, eggs, or even cereal could be found. The skeleton had known they were low on stock, but he seemed unable to find any of what he needed.There were almost no ingredients in the kitchen for Sans to make anything.

He kept looking until he finally came upon his last resort. Oatmeal. He wasn't a big fan of the stuff, but Pap didn't seem to mind it. Nevertheless, he needed to eat. He could run out and get ingredients later, but he was hungry enough to eat just about anything right now.

The skeleton's attention was drawn away from the unappetizing meal by the sound of footsteps on the floor above him. _Papy._ Undoubtedly, the skeleton had realized he had left part of his battle body downstairs, and was coming to get it. The younger skeleton placed the box back on the counter. Breakfast would just have to wait for a bit longer.  _Just one peek,_ Sans told himself, inching towards under the arch that led back to the living. _Then I'll force down some oat sludge._ _However tasteless and bland it may be._

Small blue gloves grasped the corner of the kitchen arch, and two starry eyes watched silently as heavy footsteps tread down the stairs, on the search for the remainder of Papy's new clothing. Only two or three more steps now, then the smaller skeleton would be able to see the very first parts of his bros' battle body.

 _There!_ The taller skeleton emerged from behind the corner, and time seemed to slow to a snail's pace as Sans took it all in. It seemed he had guessed right- his bro had definitely changed his apparel. The younger skeleton's eyes followed along the bottom hem of the skeleton's outfit. Black pants, thin and lanky so that they fit around his brother's form. The red belt, complete with a golden oval buckle was new- Sans didn't quite have anything like that on his battle body, but it definitely helped pull the outfit together. Papy seemed to go foregoing an undershirt, so Sans' eyes followed along the bones to the chest cavity of the larger soul, where his orange soul sat-

The skeleton's blue eyes froze on the glowing organ in the other's chest. An organ that wasn't orange.

 _That's not right._ Sans knew what his brother's soul looked like. He'd seen it more than enough to know for fact that it was orange- not the dark crimson red like the soul currently beating beneath the taller skeleton's ribs. And Sans severely doubted that his bro's soul had gone through extensive color changing overnight, just to match his brother's new outfit choice. While color changes in a monster's soul were _possible_ , it usually took place over a long, extensive period, where the monster's soul matched up with the monster's emotions and feelings over a long time, and it was never an obvious, complete shift in color like this. Which meant just one thing.

That wasn't Papyrus' soul.

And this wasn't Papyrus.

"There you are you little _shit_ ," The figure said, with vulgar language seemed to confirm Sans' startling realization. "You thought you could run?"

* * *

It took Sans a moment to recognize the foreign feeling of calmness. It came with the strange sensation of awaking peacefully, and not at the receiving end of a barked command. It was almost as if he wasn't feeling the effects of exhaustion at all, after only just three hours of sleep- the same three hours he had every night. No. Sans wasn't just not tired- he felt completely awake. Well-rested, even.

Which was how he knew something had to be horribly wrong.

Red eyes shot open in alarm as the skeleton squirmed out of the bedcovers. The panic in Sans' mind, despite being asleep only moments ago, already occupied all of the monster's thoughts.

Boss wasn't one for letting Sans sleep in. Unless he was dead or dying- and hell- maybe even if he was dying, Boss was going to make sure Sans was at his post. And the larger skeleton definitely didn't have a problem using force to do so. Which brought Sans back to realization that something must've gone horribly wrong.

 _It's got to be midday at least,_ Sans thought to himself. The light shining through the window of Boss' room was bright enough that it must've come from the buildings in town, which were only on long after the time the skeletons normally awoke for their posts. The light couldn't have been the natural illumination of the crystals of the Underground- they weren't nearly as bright. _Midday._ That meant he'd slept for at least what- eight hours? His post would be halfway done by now. No way in hell would Boss let that happen.

One quick glance behind him revealed what Sans already knew- the other skeleton wasn't still in bed. So either Boss had gotten up and decided that Sans deserved a break today... or something else had occurred. _Yeah._ _Not even on a good day._

As far as Sans could tell, there were just two possibilities to explain this conundrum. Either option one, Boss had dropped dead in the middle of his sleep, and his incorporeal spirit hadn't been willing enough to bitch and moan until Sans got up, or option two, Sans himself had been the one to bite the dust.

Of course, there was the off chance that this was all just some stupid dream, and he'd be awoken momentarily by a kick to the ribs, tossing him off the bedside, or yank of a leash- but the skeleton had already disregarded that possibility. Sans didn't dream. Or at least, not about anything as pleasant as getting to sleep late. So it was back to options one and two.

Personally, Sans was leaning towards option two. Maybe he'd somehow pissed the Boss off in the middle of the night- something petty like grabbing more than his part of the blanket or taking up too much space or just being alive- and Boss had finally snapped, disposing of him as one would dispose of any broken toy- swiftly and without a thought- probably piercing the smaller skeleton's body with a single bone, crippling his fragile being. Sure, a quick check of his soul proved that it was still beating, but who knew? Maybe this was all some weird post mortem shit.

As much as Sans hoped he was dead, he couldn't discount the possibility that Boss had died, or that there was some unseen third possibility- one that probably didn't involve a stroke of morality and mercy on Boss' part.

Well, for one, the smaller skeleton wasn't covered in the remains of a dusted Boss- so that option could probably be ruled out. That was, unless Boss had been polite enough to get up and move away from Sans and the bed before spontaneously dying in his sleep. Which, while still more likely than Boss willingly letting him sleep, was still highly unlikely.

So that just left the unknown.

 _You know what?_ Sans thought to himself, sarcasm only slightly guiding his thoughts. _Maybe Boss did get up and die somewhere else._ _I mean, the asshole always yelled at me for making a mess of the bed-_ The skeleton's silent rant was cut short as his red eyes scanned the immediate surroundings of the bed, only to make another startling realization.

 _This ain't Boss' room._ At first glance, it had seemed just like it- but looking closer now, it couldn't possibly have been. Not unless someone had secretly repainted the walls of the room throughout the night. They seemed to be shades brighter than their original dark brown color. The room may have been just as messy as Boss', with clothing randomly scattered across the floor- yet the clothing pieces were completely unrecognizable to the skeleton. Hell, the room was even smaller than Boss'- closer to the size of Sans' own room, actually.

 _What the fuck?!_ That original feeling of panic was back, along with a heavy dose of confusion, and Sans quickly kicked the bed sheets off of him. Sheets that weren't stained and soaked like the ones he had fallen asleep under, just the night before. He swung out of the bed, and onto his own two feet, backing away from the covered mattress as if it had a plague. A mattress with no bedframe- just like the one in Sans' own room.

 _Breathe. Breathe Sans._ He couldn't panic now. He had to keep his guard up. Wherever the hell he was, he certainly wasn't safe- which didn't mean a damn thing, because everywhere in the Underground wasn't safe.

 _Why am I here?_ The skeleton figured there had to be here for some reason, yet there was hardly enough information available to him to piece together the _why_ of the situation- so he decided to move onto something a bit easier- the _how._

Maybe someone had brought him here. _No- not maybe._ Somebody must've, because Sans was positive he hadn't sleepwalked from Boss' room to wherever this place was. Which meant someone had kidnapped him in his sleep- kidnapped him, Sans, for some godforsaken reason. For ransom- or maybe because of a grudge?

 _Yeah, fat chance._ Sans was sure more than a few monsters hated his guts, but he doubted any of them would go to this extent. And the idea of himself being held as ransom sounded ridiculous as soon as he had thought it. The skeleton would be stunned if Boss would even pay even a single gold to get him back.

 _In the end, it hardly really matters,_ Sans told himself. He could stay here and figure it out for as long as he wanted, but it didn't change the fact that he was still here- in unfamiliar territory, completely alone. He should be being careful- and smart. He wasn't strong like his brother. When it came down to situations like this, he was hardly strong enough to take down any monster who had been able to sneak into Boss' house and kidnap him. Which meant his only advantage was being able to think on his feet and finding a way to escape. And it just so happened that finding ways to run away from problems was one of Sans' very few skills.

Naturally, his eyes fell upon the window first. Dashing over beside the glass, the bony fingers of the skeleton tried to no avail to pry open the possible escape route. Of course it had been jammed shut and completely inoperable. No kidnapper would be stupid enough to leave the freaking window open.

 _Smash it._ The thought crossed his mind moments later. The window was probably made of everyday, conventional glass, and if Sans' bar fights had Grillby's had taught him anything, it was that the transparent substance shattered surprisingly easily. And yet... _someone will definitely hear if I smash the glass._ There was no silent manner to go about such a violent action. His captors might be alerted of his attempted escape before he could make it.

 _I can always just port myself out of here._ The words disagreed with the skeleton as soon as they passed through his head. His blinking in and out of existence, unsurprisingly, took a lot of magic. His reserves were already quite low- they always seemed to be- and the skeleton would hate to risk running out of energy halfway through a jump.

 _There's got to be some other way out of here._ Sans decided. His teleportation was a last resort failsafe. Glancing around the room only managed to dash the skeleton's hopes. The only other possible escape from the room was the wooden door- something that wasn't even worth trying. _If they remembered to jam the window, I doubt they'd forget something as simple as locking the door._

The monster paced around the room- the room that the skeleton was slowly deciding seemed more similar to a weird cross between his own and Boss'. The mattress was shoved off to the back left corner of the room. Just opposite was a box that served as the nightstand. Almost a mirror image of the items in Sans' room. To the side of the window that the skeleton had only just tried to escape was a small desk with a computer on top of it- that was something neither Boss nor him had in either of their rooms.

Right beside the doorway laid a cardboard box- just like the one Boss had in his own room. Without a second thought Sans moved to the box- spurred on by a mixture of curiosity and hope that the mystery storage container might hold some sort of help to his escape. Only a moment later he'd already torn the top of the box open, revealing its insides to his hungry red eyes.

In Boss' room, the box beside the door contained all the messed up shit he liked to use on Sans. Bondage, whips, knives, bone saws- whatever fucked up things there were, the bigger skeleton had used them all. The box held all the other skeleton required to punish or fuck Sans, depending on the outcome of the day. This box held no such things- which Sans couldn't help but be disappointed by, because if it had, then the skeleton would've have a worthy arsenal of weapons to use against his captors.

Instead, the box contained what appeared to be the most boring collection of items ever. Stacks of papers and sketches, seemingly ancient and forgotten, alongside miscellaneous metal pieces. The metal pieces were tiny, able to just about fit in Sans' hand- meaning it was impossible for the skeleton to use them to bash his kidnapper's head in.

 _Nothing. Of course._ What had he expected? A key? A note for him, explaining the exactly reasoning for how and why he was here- as well as where _here_ even was? The snow coating the ground outside the window had told Sans that they must've still been in Snowdin- or at least in the forest between Snowdin and the Ruins- but that only raised more questions about why there was some weird in-between land of his and Boss' quarters, and just why he'd woken up in it.

Sans collapsed in front of the door, trying to calm the swelling headache forming in his head. All these questions, and not a single explanation besides _kidnapping_ _?_

 _Why the fuck would someone want to capture me and bring me here?_ He asked the question again but still had no answer. It was weird. Utterly bizarre, really. The similarities between this room and those Sans was familiar with were too striking to be of coincidence. Which meant someone had purposely recreated some combined mesh of the two bedrooms.

 _Fucking strange to say the least._ Sighing, Sans leaned back, his skull meeting the solid wood of the door. A door that apparently was _not_ locked, unlike how Sans had previously assumed. The creaking sound of the door swinging into the hallway sent Sans scrambling as to not topple back with the loss of his support. 

 _...what?_ The momentary confusion of the skeleton left him dumbfounded as he stood tall, putting his two legs beneath him. _Did they... forget to lock the door?_ No, that was impossible. Nobody was that stupid. _This must just be some kind of ploy- or I've been kidnapped by the worst kidnappers in all of monster-kind._

Into the hallway his legs carried him- only to find his soul skip a beat. He'd emerged from strange contortion of Boss' and his bedroom only to find the strange recreation extended to the entirety of the skeletons' house.

Maybe Sans really had died. This whole thing was way to weird to be real life. _Shut up._ Sans told himself as he began walking down the stairs of this copycat version of Boss' house. He should just head for the exit. Then he could get out of here, head back to his _actual_ house, and pray that Boss didn't punish him too much for getting kidnapped and missing half a day of guard duty.

His desperate attempt to traverse the stairwell soundlessly failed at the third stair from the bottom. The wood creaked loudly throughout the open layout of the house, echoing through the hall and living room, and Sans winced instinctively. _Oh fuck._

There was some noise from the living room- past the stairwell, just to the left, shrouded from Sans' line of sight by the corner of the wall beside him. It sounded like something shuffling against the living room couch, alerted to Sans' escape. Panic immediately overtook the small skeleton, and he was only able to gain control of it once more when he heard another sound- one that definitely couldn't be described as _alert._

Sans waited, uncertain that he had heard what he thought he had. Sure enough, only seconds later, the same noise repeated once more. And again. And again.

...snoring?

A monster had kidnapped him, only to go to sleep afterwards and leave him completely unguarded? Sans had thought that only one monster in the Underground could be capable of such laziness- him.

A bit bolder now, the skeleton moved down the remainder of the steps Feet landed on the carpet floor of the living room safely, in what was shaping up to be possibly the most uneventful escape in the history of ever. Sans' red eyes followed the sound of the gentle snores- directly to the couch, where the tall skeleton Sans had known since he was a baby slept peacefully.

"Boss?" Sans whispered, choking on the word. There was no way this could be him. The skeleton on the couch was wearing an orange hoodie, with no dark black and red armor on him. He was calmly resting late into the day, at a time when his brother would surely have arisen in order to do his job. And a certain scar across his left eye was missing- a defining feature of Papyrus appearance since he had gotten it when they were young.

So how was he currently looking at someone who looked exactly like his brother right now without that same scar?

Sans walked closer to the sleeping figure and leaned towards him. Maybe the scar had faded away a bit. It did that at times, usually whenever Boss was especially relaxed, which was something that rarely ever happened. Yet when he leaned over to examine the skeleton's eye, he hadn't expected to wake the larger monster up.

Two eyes squinted open and met with Sans' own. The smaller skeleton froze in terror, while the figure below him managed a lazy smile.

"Morning already?"

**Notes for the Chapter:**

> ~Edited 4/9/17~  
> I'm currently in the middle of editing most of this story.  
> Hope you still enjoy!


	2. Chapter 2

"Morning already?"

Apparently this skeleton- who certainly was not Sans' brother, was a much lighter sleeper than his snoring had suggested. Sans jumped back, desperate to put some distance between the two skeletons as hazy orange eyes were peeled opened and those words were spoken.

 _Just had to get curious, didn't I?_ Sans mentally scolded himself for his idiocy. Of course this hadn't been Boss. He would never be caught dead sleeping during the day. Why had Sans been stupid enough to think otherwise? 

"What? I startle you?" There was a chuckle, and red eyes shot back to the couch to land once more on the other skeleton. Surprise was the only thing that startled Sans, as the shock came over him with the realization that other monster was still loafing peacefully in his spot on the cushioned couch. The larger monster’s eyes were closed carelessly; and an easy, carefree smile rested upon his face as his body remained motionless. It was a smile unlike any that Sans had ever seen before, warm and happy and perfectly content, not worried about the slightest thing. If it was some elaborate ruse designed to throw Sans off-guard, it had done so perfectly, because the shorter skeleton had been expecting the other monster to attack when he'd discovered his attempted escape.

"Scared you that bad?" The amusement in the skeleton's voice seemed strangely honest and truthful. There was another chuckle from the larger skeleton. "Sorry bro," Sans said nothing, paralyzed by his fear and uncertainty. This monster must’ve still been thinking that Sans was someone else. Which meant that if the smaller monster said anything, his voice would certainly betray his true identity.

The skeleton shifted in his space on the couch, and the vertebras of his spine, settled during a long night of sleep, cracked with his movement against the fabric sofa, "Do we _have_ to go to our posts today, bro?" Again, Sans said nothing- no idea how to respond, or even if he should. Groaning, the other skeleton turned his head and peeked one eye open to look at his brother- only to have both eyes shoot open when he saw who was really there.

The larger skeleton scrambled to push himself up from the couch, before pausing awkwardly, two arms beneath him, holding his body halfway up. "You're... not my brother," The kidnapper's revelation managed to somehow seem both dumbfounded and unnaturally calm, but the observation had already been more than evident to Sans.

"Who the hell are you?" Sans finally found his words, as well as his anger for this monster who was sleeping down here, acting as if he hadn't just kidnapped him the night prior. Even with his brewing rage, Sans’ mind couldn’t help but acknowledge the uncanny resemblance this monster had to Boss.

"Watch the language," The skeleton's threat was so unintimidating that it was almost comical to the shorter skeleton.

"Answer the fucking question."

"I said watch your language."

"And I said answer the fucking question!" Sans growled back angrily. He didn't have time for these stupid games. He just wanted answers out of this skeleton- this skeleton who Sans was starting to suspect was completely incapable of doing something so difficult as kidnapping a sleeping monster from the house of the Captain of the Royal Guard. Looking at him, he must’ve been some mindless henchmen of whoever had actually taken Sans- which meant that the eerie resemblance this monster shared with Boss was nothing more than a coincidence.

The larger skeleton sighed after a short pause, giving in to Sans' anger. Taking a deep breath, the skeleton looked back up at Sans with a sort of half smile- different from his previous one in a way the Sans couldn't quite describe. For a moment, the larger skeleton said nothing. He did nothing but stare dumbly, with the lazy, half formed expression on his face- and it didn't take long for that to wear on Sans' thin patience.

"What are you doing?" Sans demanded from the other skeleton.

"Thinking," The word answer was spoken by the taller monster as if it were obvious. 

"I doubt you need to do much thinking about your own name," Sans was ready to begin pooling his magic together for an attack. This monster was clearly stalling. "No how about you answer the question before I-"

"Papyrus," The name was thrown about so casually, the larger skeleton making the claim so easily, that it was as if he had hardly even heard Sans' threat. "What about you?"

"Bullshit," The smaller monster had no trouble calling out the other skeleton's obvious lie. "You're not Papyru- Boss," Sans instinctively corrected himself, used to never using his actual brother's name. Boss hated it when Sans did that. Silently, the smaller skeleton glared at the other, demanding an actual answer.

Orange eyes looked questioningly at the smaller skeleton, but it didn't take long for Pap to realize that the staring and glaring contest between the two of them wasn't resolving anything at all. Ignoring the strange name the other monster had used for Papyrus, the skeleton began to talk once more. "And you're not Sans," Red eyes faltered for a minute, confused. "Even though I imagine that'd what your answer to my previous question would've been."

 _What was this imposter talking about?_ Sans questioned to himself as the 'Papyrus' on the couch snorted. "While you do kinda look like him, you two act nothing alike."

 _You two?_ _What the hell is this fake talking about?_ "Why don’t we cut the bull?” Red eyes glowed in all seriousness at the other monster. “Where the hell is my brother?" Sans demanded the impostor.

"That's actually my line, I believe," Unexpected chills ran down Sans spine as he suddenly found himself on the receiving end of the glare from one brightly glowing- no- one _burning_ orange eye. The stern and unwavering look on the larger monster's face convinced Sans that he may have underestimated this foe- and that this monster might be capable of more than the skeleton had thought.

The two continued their interlocking glare for what seemed like eternity as Sans fought against the thoughts of what this monster may or may not be capable of away from his mind. Neither said anything, and yet both demanded the answers that neither were able to produce.

It was the skeleton in the orange sweatshirt who finally ended the exchange. One blink and his glowing orange eye disappeared, replaced with his calm, lazy pupils. He shoved bony hands into sweatshirt pockets and leaned back into the couch comfortably, seemingly ignoring Sans' presence for a moment. Only then did the answer to both of the monsters’ questions strike the larger skeleton as a wave of understanding overtook him. 

 _"Timelines,"_ The skeleton mumbled the word to himself, quiet and whispered but said with absolute certainty and confidence.

"What?" Sans was unsure if he'd heard the larger skeleton right.

Papyrus glanced back to the other monster. "Sans," His gaze drifted off the skeleton as he spoke the name, like his mind was traveling with it somewhere else- far away from the room he was in right now. Uncertain how to react, all Sans could do was narrow his eyes at the skeleton who was lost in thought.

"So you're... Sans." The dramatic moment created by the skeleton's silence was ultimately butchered by the obvious statement.

 _Well yeah, no shit._ Sans was sure he didn't need any confirmation on his own name- it was only the name he had lived with his entire life. Well, mostly- but that wasn't important. "Clearly. But there's no way in hell that you're Boss."

The larger skeleton shook his head, "I may not be whoever this... Boss is, but I'm certainly Papyrus. Or at the very least... _a_ Papyrus."

 _A Papyrus._ _As in there being more than one._ Sans had thought he’d seen a lot of crazies in the Underground, but this one, right here, definitely took the cake. "What the hell are you rambling over?"

"It’s the timelines," The larger skeleton said once more, as if that explained everything- as if the statement even made some sort of sense to any sane monster.

 _What the hell are timelines?_ _And what the hell do they have anything to do with this?_ Flaming red eyes glared as the smaller skeleton opened his mouth once to threaten the other monster into making sense- but that other monster had already read his thoughts.

"Relax," The other skeleton had returned to lying on his back and staring at the roof above them- not even looking at the other skeleton. "I’ll explain everything in a second. Just realize that you're gonna be fine. You're not in any danger or anything."

 _Because I’m gonna trust the rambling lunatic when he says not to worry._ Of course Sans was in danger. He was in some weird version of Boss’ house with a crazy, delusional skeleton claiming to be Boss- no, _a version_ of boss- and repeating meaningless phrases like a psychopath. Not to mention the fact that he had more than likely been kidnapped from his own house to be brought here. If that wasn't being in danger, then Sans didn’t know what qualified.

"What the fuck are you talking about?" He was fed up with this shit. He wanted answers. Boss’ impersonator only looked at him as if he had said something he wasn't supposed to, before sighing. 

"Where do you think you are, right now?"

"What?" Sans stared intensely at the other monster. That sounded less like an answer to Sans’ questions and more like yet another one.

"Where do you think you are?" The skeleton in an orange hoodie repeated.

Sans gritted his teeth. He wasn't getting an answer. "Listen here. You're going to tell me what the hell is going on, or else I'm gonna cut that skull of yours clean in half," He wasn't lying. This impostor wouldn't last a second against him in a fight. Sans didn’t care if he had a mean glare or not reserved for serious moments. He could jump him from his position right now and have him beat before the larger skeleton could even sit up. “Now how about you start-”

"Humor me," The lazy skeleton cut him off from another outburst. "Just tell me. Please." Sans froze, surprised.  _Please_ wasn’t a word often used in the Underground. It was a sign of weakness- a clear cut message that you were depending on someone else for something. Yet here this monster was, saying it like it meant nothing.

 _Who was this guy?_ Sans thought. He didn't seem like much, but Sans had never seen someone act like him in the Underground. Monsters like that didn’t typically last long past childhood. This skeleton hardly seemed capable of kidnapping him. _And while this can all just be a front... something to get my guard down... I don’t know. Something about that feels wrong._

"I'm in- in a house," Sans found that he was stuttering the words out of his mouth before he knew what he was doing. He half expected a sarcastic comment from the other skeleton for the weak start to Sans’ thought, yet instead he was given an encouraging nod as the other “Papyrus” motioned for him to go on. "It's an almost perfect copy of Boss’. But it's different. Everything's..." Sans paused, unable to find the right word to describe it.

"Better?" The other skeleton offered. "Nicer?"

"...everything’s different." It didn’t feel right to describe the house any other way.

"Right," The skeleton on the couch seemed to expect an answer along those lines. Without so much as a warning, he got up off the couch. Sans flinched at the sudden movement, expecting an attack- an attack that never came.

Sans looked back at the monster in front of him. He finally had a better look of him. He was a bit shorter than his brother, and his orange hoodie was a bit too large, the bottom of it hanging over the skeleton's grey shorts. While Boss had sharp fang like teeth just like Sans and most of the monsters he knew, this monster had nothing of the sort, his teeth being flat.

 _Could this really be some different version of my brother?_ The idea was ridiculous. He couldn't believe he was beginning to fall for something so stupid. That was obviously some sort of distraction from whatever was really going on.

 _…And just what was that whatever?_ How else could he explain another skeleton living in the Underground who looked just like his brother?

Sans was pulled from his thoughts as he noticed the monster in question begin to walk away, making a not so hasty escape.

"Where do you think you're going?" Sans growled. He still wanted answers, and there was no way was he letting his one way of getting those answers literally walk out the door.

The monster only paused. "Out," he motioned to the door. "It's a beautiful day outside." Sans began to pool magic for an attack. This impostor wasn't getting away.

"You're welcome to come, you know," He offered, pausing with his hand on the door.

The offer caused Sans to hesitate once more. Politeness wasn't exactly something he was used to. Just as he did, the door swung open, and the taller monster walked back into the Underground. If he wanted answers, Sans was going to have to follow.

* * *

Snow. His first step outside the door produced the familiar crunching sound of the snow being crushed beneath his feet. And only one place in the Underground had snow.

 _I really am still in Snowdin,_ Sans had thought just as much from seeing the snow outside the window in imposter’s room, but the fact sunk into the skeleton’s mind much more as the white snow crystals crunched beneath his shoes.

How was it that a mirror image of the Boss' house be built in the same town and not be noticed by the skeleton? Every day, Sans walked to his post. He’d never seen anything like that at all.

Sans tore his gaze up from the ground and threw it on the skeleton he had followed out of the house. "Hey!" He called out to the monster, yet the fake made no attempt to slow down so Sans could catch up. The skeleton with the orange hoodie continued walking to the center of town. Sans ran to catch up. The lazy skeleton could apparently move fast when he wanted to, and his longer strides certainly didn't help. When Sans finally reached him, the two were already in front of Grillby's.

"Hey!" The smaller skeleton yelled again, right behind the other skeleton. He was tired of being ignored. If he had to use force to get answers, he sure as hell would. The larger skeleton stopped suddenly, and Sans skirted to a screeching halt in the snow in order to avoid crashing into the back of him. The other monster turned to face Sans, looking down at the shorter skeleton.

"Look around," The imposter told Sans.

"Why?" Sans already knew where he was. He had this place memorized like the bones of his hand. He knew everything about Snowdin that there was to know. Why would he need to look?

"Just do it," Sans gritted his teeth at the skeleton’s words. He was used to the Boss telling him what to do but he didn't like the idea of this imposter doing the same. Yet the way he said it... whenever his Boss told him to do something, there was some sort of threat interlaced into the order. A punishment if he decided to disobey. It didn't seem that way with this. It wasn't phrased like a command- like something he had to do in fear of punishment. It was... different, because it seemed like less of an order and more of a request, that Sans could ignore if he decided to.

Despite already knowing what he was going to see when he did so, Sans looked around the town. For a moment, he saw the same things as always. Sans saw the buildings in town square, large and bulky, polar opposites of the thin and skinny forest trees behind around town. He saw the pathways in the snow, defined by the footsteps of passing monsters. He could see all the usual Snowdin sights- but it took another moment for skeleton to realize what he was failing to identify.

Red eyes widened. This… wasn't Snowdin, or at least, not the Snowdin the skeleton was used to. It was just like the house he’d awoken in- some sort of weird, changed version of the quiet snowy town he knew.

"Different, isn't it?" The other skeleton asked, but the impostor seemed to have already have expected as much.

 _Yeah._ Sans thought to himself, unable to say the word aloud. He was in shock.  _Everything was different._ Well, not everything. Like Sans had first realized, all the big things remained. The building, the surrounding plant life, the pathways- they were all in the same place. The differences were the smaller things. Things that went unnoticed with just a quick glance over.

For starters, Grillby's was no longer Grillby's. The trashy bar that had been one of the few places Sans could find a meal was replaced by a colorful and fancy place that was called Muffet's.

The dead tree in the center square was instead alive and decorated with bright lights, with boxes wrapped like presents underneath the tree. Tiny tags seemed to be attached to the boxes, but nobody was taking them despite the nonexistent security surrounding the items.

The building back the way the pair had come- the Library- or Librarby, as it said on the sign above the entrance- was open. Not abandoned or boarded up, like the skeleton was familiar with.

It seemed like all of it was different. Every building Sans had passed every day for the last who knows how many years, was nothing like what it had been before. They looked more welcoming... and seemed… nicer. Just as the other skeleton had said.

Even the temperature reflected that tone of the town. The biting cold that Sans had always associated with Snowdin was gone. It felt warm. Too warm even, for Sans at least. The two layers of clothes he always wore to protect himself from the bitter cold seemed redundant.

There were the monsters too- outside, strolling about town, without a worry in the world. Sans recognized some of their faces as the same as the Snowdin townsfolk he was familiar with… yet even they were different. Just being outside rather than in the safety of their own homes was something unprecedented. Not to mention their outfits, their actions, their expressions, all of it; they all seemed gentler and... warmer. Where there were typically glares and frowns there were instead smiles and waves. Where there were always death threats and warnings, there were morning greetings.

It shouldn’t have surprised Sans when the smiles and waves disappeared, along with those cheerful hellos. It shouldn’t have thrown the skeleton off when confused stares and looks began to be thrown in his direction. He felt so out of place here, because he _was,_ and all of the other monster were starting to pick up on that.

What usually helped him fade into the crowds, looking just like everyone else, accomplished the exact opposite now. His black and red clothing, a pretty common look in the Snowdin he knew, was nothing like what the townsfolk wore. It contrasted starkly with the light hues of their outfits- sucking all of their attention toward Sans like some sort of void. The skeleton’s threatening demeanor only made sure the other monsters kept on staring. The smaller skeleton was sure all of them couldn’t help but wonder just what this strange monster was doing here.

Sans had always been taught that he needed to protect himself with every expression and word. He’d learned how important it was to build walls around himself to stay safe. He knew all too well that if he didn't, he would be taken advantage of and used.

And it had always been true. Because the one time he hadn't been able to build those walls, to protect himself from an outside force, he had been used. And it had been from his very own brother, the one monster Sans couldn't bring himself to lock out of his life. He couldn't build that wall, and he got hurt because of it. And it was his fault.

Yet those walls, once the only thing that had kept him safe, were now the exact thing that made him an outcast here. His built-up personality, made in a desperate attempt to make other monsters fear him and therefore leave him to be, hardly worked with the monsters of his Snowdin, nor did it here. Yet that was for two very different reasons.

The monsters Sans was familiar with were unintimidated by the skeleton’s half-baked charade. The could see right through his tough looking clothing and cold glares and find the fear and terror buried beneath it all.

Yet here the monsters were obviously not used to such things. And because of that, their curiosity was free to question the foreign looking monster and prod at him with their eyes, unrestrained by the fear that doing so might draw attention onto themselves.

"Hey," The skeleton towering above him said in almost a whisper, jolting Sans out of his thoughts. "You're alright," He rested a hand on the smaller skeleton's shoulder, giving him a warm smile. It was almost like he could sense Sans' doubts.

The confusion and panic from before flooded over Sans' mind, and he pushed away from the larger skeleton, his hand falling back to his side. He didn’t like this feeling. This uncertainty. He didn’t like _this_.

"What the hell is all this?" Sans could see the other monsters whispering to each other, some gasping in shock as the skeleton spoke. They were talking about him. It was so obvious. Pathetically obvious, but Sans didn't care. They could say whatever the fuck they wanted. He couldn’t care, because he was used to people talking behind his back. That was just something else he had learned to deal with. That was another thing he lived with. What he couldn't live with was waking up one day and finding himself in this completely shifted version of his reality.

He just wanted answers. That’s all he’d asked for. That’s all he wanted, and this larger skeleton had refused to give them to him every time he asked.

The impostor looked around at the staring monsters. They seemed to look away as he did so, almost as if they felt bad for being caught. "We should get out of here."

"I want answers," Sans was tired of this other skeleton’s bullshit. First in the house. Now outside, where Sans had done everything the other monster had asked. He’d been cooperative a majority of the way through, and this skeleton still refused to answer the simple question of what was going on.

Sans wasn’t moving from his spot until he got that answer, and his two feet, planted into the snowy ground beneath them, made that point very clear to the taller monster. The larger monster smiled weakly, acknowledging the second skeleton’s stubbornness. "…Alright,"

 _Finally,_ Sans thought to himself, as he let out a sigh of relief internally. Before the skeleton knew what was going on though, the imposter began to walk away once more.

"Hey!" Sans yelled again, "Get back here!" The other skeleton hardly even hesitated, and the door into Muffet's swung open as the he walked in, leaving Sans with not much of a choice once more. Gritting his teeth tight, Sans walked in after the skeleton, hoping that Muffet’s was not like the Grillby’s he was familiar with.

* * *

Sans would have been surprised if there was ever a place more unlike the shithole that was Grillby’s than Muffet’s. The bar he was familiar with was old and filthy, stained through the years by mud and blood alike. The food served was about as rough and undesirable as the patrons that went there, night after night. The skeleton only ever went to the bar because it was the only place in Snowdin with cheap enough food that he could afford with his meager pay from Boss. A pay which he only ever received if Boss was feeling especially _generous_ that week. Otherwise… well, Grillby had always been open to different sorts of payment from Sans.

Muffet’s seemed nothing of the sort. On first glance, the bar hardly even seemed to be that. The sweet smell of pastries and sugary treats filled the air, making it seem more like a bakery than anything else, yet sitting at the opposite end of the room, just like in the Grillby’s Sans was familiar with, was a bar complete with stools.

The place clearly had some sort of fascination with the color purple. It was as if a painter had accidently spilt the color across the room, and decided that was good enough. The walls, chairs and booths and the counter were all separate shades of the color. The floor of the bar was even checkered white and purple.

There were a handful of monsters filling the room, sitting at booths and chatting amongst themselves while eating what seemed to be croissants and doughnuts. Yet the skeleton Sans was looking for sat by his lonesome at the bar, talking to a purple spider- the bartender- who Sans could only assume to be Muffet. Striding across the room, gaining only momentary glances from the other patrons of the place, San began to sit on a stool beside the imposter before getting a curious look from the bartender.

"You bought your brother today?" She asked to the other skeleton, busy making a drink with two of her six hands.

"I'm not-" Sans began only to be cut off by the larger monster.

"Yep," The skeleton said. The pink spider shrugged and smiled. She looked at Sans.

"What can I get for you, sweetie?" Sans decided to ignore the fact that she called him sweetie. He was liking this place less and less.

"Whiskey- on the rocks," He answered bluntly, defaulting to the one hard liquor he was familiar with from back at Grillby's. The spider's eyes widened in shock and she glanced back at Papyrus, unsure. The skeleton only shrugged.

A minute later both of them had a drink in hand. Sans got his whiskey and downed it easily, earning another surprised look from Muffet despite the fact that the drink tasted like it had been watered down. The other skeleton waved Muffet away, thanking her as he did so.

"I thought you said you weren't my brother?" Sans asked.

"I'm not. And you're not mine. It's just a heck of a lot easier to explain," Papyrus leaned back, sipping on a glass of liquid that Sans couldn’t identify- yet it smelled strongly of alcohol. "If some skeleton who looks almost exactly like the Sans everyone in the town knows suddenly appeared one day, that would raise a few eyebrows, wouldn't it?"

"Yeah..." It did make sense. Sans didn't really feel like answering questions that even he lacked the answers to yet.

"Though," The skeleton took another sip, before placing the glace back on the table. "By the looks of it, you've already caught the attention of a few people here."

"And do you care to explain where exactly is _here?_ Where am I?" The fact that he had woken up in some weird version of his town where everything and everyone was changed was eating away at him.

"Snowdin," The other lazily replied as he traced the rim of his drink with a bony finger.

"You know what I mean," Sans said, not up for any bullshit. His head was spinning in circles, and getting answers was the only way to resolve that. "You said something about timelines."

"I did," Another sip as a steady hand rose the drink once more to his mouth.

"Would you care to explain?" 

The larger monster sighed, as if he was dreading the topic. "You're not supposed to be here," Sans glanced at the other. That was one way to start a conversation. "I don't even know how you're here. Or how any of this is possible."

"Do you have any answers at all?" Sans bit back. He'd hate to have followed him all this way for nothing.

The skeleton took another, longer sip of his drink. "I think- I’m almost positive that this has something to with our separate timelines.”

“Which are?” Bringing it back up once more didn’t make the skeleton understand it anymore.

“They’re… a lot like alternate worlds, similar to each other is some ways, yet different in others- parallel universes, if you will.”

"What?" Sans almost laughed at the statement. That had to be some sort of joke. This skeleton had to be absolutely mental if he thought that he was gonna buy that weak explanation.

"Each timeline- or universe- is made up of a different order of events and choices taking place in certain ways with certain versions of ourselves. They can range from drastically different, to indistinct from one another,” Slowly the skeleton placed the glass before his mouth, taking a long and drawn out sip. “…My current presumption is that you are from one of those universes." Sans couldn't believe it. This skeleton _was_ being serious.

"And you think I somehow came from there to here?" Sans shook his head. "That has to be the most farfetched bullshit I've ever heard."

"Is it?" The imposter didn’t even look at Sans as he asked the question.

"Yes!” Sans replied instantaneously, with absolute certainty. “You do realize how crazy you sound right now?"

"Well then, how do you explain all this?" The skeleton motioned to him. "You certainly aren't my brother, but here you are, and my brother is nowhere to be found. Your entire version of Snowdin is gone, and instead replaced with this one."

"Yeah, well..." His voice trailed off. It was undoubtedly a shitty explanation in Sans’ eyes… but it did manage to explain what was going on. Or at least somewhat. "How do you know all this?"

"Huh?" The skeleton froze for a second, finger stiffening on the top of his glass. He clearly hadn’t prepared an answer for that question. "You know- research."

"Research?" It wasn't really even an answer to the question. It was more cryptic and vague than anything else the monster could’ve said.

"It doesn't matter." The _alternative timeline_ Papyrus said, ending the topic. He clearly didn't want to talk about it. The two of them sat silently at the bar as the larger skeleton finished his drink.

 _Parallel universes._ Sans couldn't believe it. Here he was in some happy version of his own reality where everything was okay- no, better than okay- great. It was almost like all his dreams had come true. He was in a place where everything that was wrong with his own life had somehow gone magically right.

Without warning, Sans burst out into a hysterical fit of laughter. The Papyrus beside him jolted. The larger skeleton didn't seem to know what was going on. People in the booths all around the bar turned to look at him. Even Muffet peered out of her door in the back to see what the noise was all about. But Sans couldn't stop. He didn’t even know if he wanted to. Sans could feel his eyes start to water as the random bout of laughter continued, but he forced himself not to cry.

 _I'm crazy._ _I have to be crazy. What else could possibly explain all this?_ Sans knew that had to be the truth. Here he was, listening to some cross universal incarnation of Papyurs- or Boss- in this alternative version of the town and home he had spent years in, while other monster ate doughnuts and croissants at a bar, and the other skeleton talked to him about various versions of himself and everything he’d ever known.

 _I've finally lost it._ It was definitely safe to say at this point. _I’m a fucking loony._

The larger skeleton awkwardly patted Sans on the back, unsure what to do to comfort him in his current state. The only real remedy was time, and it took only a bit of it before the monster’s outburst came to an end. The other patrons and customers of the half-bakery half-bar began to turn back to their conversations as the frantic outburst stilled, and the Papyrus beside Sans reached behind the counter, a bony had searching for something.

"Here," The skeleton slid a yellow bottle to Sans. "It's good. Usually cheers me up."

Sans looked at it before picking it up and bringing it to his mouth. His hand tightened around the yellow bottle. He expected the taste of mustard, yet he was startled when he tasted something much sweeter.  _Honey?_  Sans questioned, moving the bottle away from his mouth, a dribble of it getting on his chin. It wasn't bad. It was pretty good actually. Not as good as mustard, but it was good.

"Muffet usually keeps of stock of it in the back for her pastries," Papyrus explained, despite the other monster not asking for once. "Though I ask for it so much, she just decided to keep a bottle up here for me." He reached over and grabbed it, taking a swig for himself. Finishing it off, he set the empty bottle on the bar. "Pretty good, huh?" 

Papyrus sighed and leaned back as he began to talk once more, not waiting for the other monster to reply. "I know it's a little much at first, but you'll get used to the idea. Or at least, I did." Sans didn't think he would ever get used to this.

"I can’t- can’t quite believe any of this," Sans managed to croak out, still fighting the urge to break out in hysterical howling once more. "You’re… You're nothing like my brother. The two of you are so different, I have trouble imagining you both sharing one name."

"And you're very unlike my own," Papyrus admitted. "Though… there are a few similarities between you two."

"Huh. There's a surprise. You're like the exact opposite of Boss." Sans laid his arms and skull on the bar to rest.

“You… uh… you keep calling him that,” The larger skeleton clearly felt a bit unsure about the topic. “Care to explain?”

“You… you wouldn’t understand,” Sans knew it was the truth. “The rules of my universe are clearly nothing like this one, to say the least.”

"Well… you could tell me,” The skeleton casually suggested the topic as he idly fidgeted with his empty glass, balancing the edges of its bottom on the bar with a finger.

"Huh?" Sans looked over at the other skeleton.

"Tell me. What's your universe like?" Papyrus couldn't help but be curious. This Sans in front of him was still a big transformation from his own. He wondered what exactly his universe was like if it made him into such a… _changed_ version of his little brother.

"Uh..." Sans wasn't used to having to answer other monsters' questions. Most monster to monster interaction in his universe was limited to angry insults, threats, or orders, depending on whoever Sans was interacting with. "It's... It’s really nothing like this."

"Well there's a shock." Sans instinctively glared at Papyrus for his sarcastic comment yet he paused once he saw the smile of his face. The joking expression told him the sarcastic remark had been meant as more of a playful jab at the skeleton than anything else- something else that seemed exclusive to this ‘timeline.’ "Monsters are a lot meaner there, aren't they?" Papyrus asked.

"What makes you say that?" Sans knew he had probably come off as a dick. Not that he wasn't.

"You look like shit," Papyrus said. Sans only gritted his teeth at the insult- he’d been the victim of much worse.

"Thanks.”

Papyrus shook his head immediately, realizing his mistake from Sans’ tone of voice. "What I meant to say was that you look terrible."

"Oh. My bad. That’s just fine."

"I mean-" Papyrus sighed, knowing he wasn't phrasing his thoughts right at all. "You look like you’re in rough shape. You’re pretty beat up."

"Huh?" Sans didn't think he was that bad. He’d been in much worse conditions. "Am I?"

"Yeah. You've got scars and cuts all over you." Papyrus said, instinctively reaching out to touch the freshest and most obvious cut just as Sans flinched away from his touch. It was the one on Sans’ check, and the skeleton could feel the temperature of the bone flare up in a mixture mock pain and embarrassment, remembering how he had received just last night from his brother.

"How bad is it?" The skeleton said, pulling away from Sans after receiving the clear message that the skeleton didn’t want to be touched.

“Bad enough,” Sans replied, pulling away from the conversation, unwilling to talk about the conditions he’d lived with for years. It was bad enough that this other monster was here, fussing over the smallest injuries, but Sans wasn’t about to give this skeleton another reason to pity him.

“How bad?” He repeated the question to the shorter skeleton.

“It’s manageable.”

“That’s not much of an explanation,” The larger skeleton answered, pushing Sans for more. The other skeleton’s only reply was the silence of having none.

“Please,” The taller monster added on after a few seconds of silence when it became clear Sans wasn’t going to give him a response. “Please tell me.” There was that word again- that desperate sign of weakness, used casually by the skeleton as if it meant nothing.

 _Why is it that I even want to tell him?_ Sans asked himself, glaring straight ahead at the back of the bar while pleading eyes bored into the side of his skull. _It’s not like telling him anything will accomplish anything._ The logic behind the thought did little to rid Sans of the irrational desire to reveal the terrors that was his Underground to this seemingly kind version of Boss that he knew next to nothing about.

"I live in a universe full of killers,” The words came out before Sans had even realized he had decided to say something. “It's every monster for themselves."

"That's… depressing."

"The only thing you can be sure of is the fact that you'll get stabbed in the back. By anyone. And everyone." Sans' eyes were still locked to the bar in front of him. He didn’t want to meet the other skeleton’s. He’d known the monster for little less than an hour, and he could already tell by the skeleton’s tone that his eyes were full of nothing but pity for him. Disgusting pity, which only made the skeleton feel even more incompetent. "So the only chance for survival you have is to not get too close to anyone… or to stab them in the back before they get the chance to do the same to you."

“What if… what do you think would happen someone from this universe went over to yours?" Sans finally looked over at the Papyrus, seeing his eyes not full of pity but lost in a trance of thought. It was a weird question to ask, but he seemed to be serious.

Sans felt like laughing. "Well, they probably wouldn't even last a day," Papyrus' expression soured as he frowned in thought, staring right on through his empty glass.

"What’s your Papyrus like?" Sans found peace in silence once more. He didn't want to talk about Boss with this version of him. And it didn't have anything to do with the fact that in these last few minutes, this Papyrus had treated him better than his brother ever had. "If you tell me about your brother, I'll tell you about mine." Papyrus said, deciding that a deal with the skeleton might tempt him into talking.

Despite him trying to keep it down, curiosity rose to the surface of his mind. He _did_ want to know what this universe's version of him was. The idea of him living in this world, wearing bright, happy colors and being nice to everyone seemed so absurd. Then again, so did an orange hoodie wearing, lazy and nice version of his Boss.

"Fine," Sans agreed, losing the battle to his newly untamed curiosity. "But you go first."

"Deal." As Muffet came out from the back, the skeleton beside him motioned for a refill. The spider bartender refilled his glass as the Papyrus began to tell Sans about his own version of him.

"He's small, for a start. A bit shorter than your size, maybe. Way too energetic," Papyrus took his glass from Muffet, and the bartender nodded to him before leaving to check in with the other patrons of the bar. "I can't give him anything too sugary. Especially chocolate. I’m sure he’d implode,” The skeleton sipped on his newly refilled glass. “I remember… this one time, when I gave him coffee. I wasn’t sure what I was thinking then. I probably wasn’t.” The skeleton chuckled softly, but his laughter seemed devoid of any sort of humor or enjoyment. “Needless to say… it didn’t end well.”

“What else?”

“His favorite color is blue. He always wears this blue bandanna that… that he got when he was younger. He's got big bright blue eyes, too- with star shaped pupils whenever he’s happy- which is almost always," Papyrus smiled sadly. "He's nice. Really nice. To everyone. It’s some sort of unconditional kindness towards everyone that I could never imagine myself having," Papyrus sipped once more on his drink. "He's seriously the best brother I could ever hope for."

The sadness in the skeleton's voice was evident to Sans. It was worry, a perfectly reasonable and logical reaction when someone you care about is in unknown danger. This Papyrus didn't know where his brother was. The younger skeleton had been replaced with- well, _him_. Which meant this Boss’ Sans wasn’t here and Sans himself was.

Yet Sans just still couldn't get the idea through his thick skull. Worry for someone besides yourself- yet another weakness that needless endangered yourself. Worry was never shown in Sans’ universe, or at least, worry for someone else. Yet here it was, out on the table for him to see. Open for him to take advantage of. To exploit, if he so chose.

As odd as it was, Sans felt jealous of this universe's Sans. Boss would never be this worried about him disappearing. Nor would he ever speak this highly of the skeleton to someone else.

Boss would probably be only annoyed and angry. It wasn’t even that hard to imagine the situation now, his brother waking up alone in his bed, clutching a leash that attached to nothing. His Boss frustratingly searching the house for him, planning ways to punish him for his disappearance. He'd be annoyed once he found no Sans in the house, but not worried. He wouldn't really care. He might even be happy. He had always been upset at Sans for "leeching off of him" as he phrased it.

Sans looked at the worried skeleton next to him. He was smiling, yet Sans could see right through the act. Orange eyes stared grievously at the wooden walls of the bar, yet they were clearing focusing on something beyond them. The solemn expression he wore on his face reminded Sans a bit of Boss, oddly enough, despite the fact that the two of them couldn’t be farther from one another.

Without much an idea of what he was supposed to do to cheer the other monster up, Sans began to mimic the skeleton's earlier moves, awkwardly patting Papyrus’ shoulder. The shorter skeleton had never been one for soothing other monsters. At any rate, it seemed to help as much- or rather, as little- as he had expected. Sighing, Sans let his arm drop back down.  _Welp. I tried._

"So... I guess you want to hear about my Papyrus, huh?" Sans asked, hoping to change the conversation's focus. Maybe if he started to talk about something else, Papyrus' mood would get better?

"Sure,” It was hardly a very enthusiastic response. 

"My Papyrus is the leader of the Royal Guard. He's one of the strongest monsters in the Underground," Sans began. "He wears this red and black armor that makes him look tough and scares away all the weakest monsters so he doesn’t have to deal with them. He's got a scar across his left eye, something he got when we were younger. He- uh..." Sans trailed off, unsure what to add. He didn't want to say anything about what the two of them did, or how Boss treated him. If this Papyrus knew that stuff, he'd probably figure out that he was just as sick and twisted as everyone else in his universe. But he had no clue what else he could say besides that.

 _Do I really know nothing else about him?_ Sans thought, not believing it. He spent every day of his life with him, how could he know so little about his brother?

"He's… he’s terrified of water. Like rivers and stuff. He won't go anywhere near Waterfall," Well, that, and because of _her..._

"So, he's a killer too?" The skeleton seemed to have ignored Sans’ last comment completely.

"Well…. yeah."

"That's what I thought." The skeleton sighed. "And I guess he’s not very nice to you, either, is he?"

"...No," It pained Sans to admit it aloud, but beside him, the larger skeleton hardly looked the littlest bit surprised. Though with Sans’ reply, Papyrus’ _everything-is-fine_ front seemed to crack and peel away in layers, the smile on his face being wiped away to match the grave expression in his eyes.

"And the collar?" Sans squirmed anxiously on his stool as the larger skeleton drained the rest of his drink and let his arm fall loosely to the bar counter, setting the empty glass back down. Something told Sans that the other skeleton had figured it out on his own. Yet he had still asked the question.

Sans really didn't like to talk about the collar. It was one of the reasons why he made sure to always wear his jacket- the white fur collar was usually able to hide it from view. The skeleton wasn’t even sure how the other had noticed it.

"Please," Sans could sense desperation in the monster’s voice as he adjusted his collar to hide the embarrassing accessory. The act was completely gone now. Sans saw right through to what it was trying to cover up. The other monster was just the tiniest push from tears. All of his body language was a tell for his emotions. His broken expression, distraught eyes, and tapping fingers- all indicators of the hidden torments tearing away at the insides of this one skeleton.

And Sans had still been unable to put two and two together to figure out what those torments _were._

"I need to know," The larger skeleton was pleading.

“…” Sans still couldn’t find the will or words to say what the other monster was asking of him.

“Please. Just… please. Tell me.” The skeleton sounded as if he was begging for his very life. “Whatever it is… However bad it may be… I just… I just have to know.”

“…You asked why I called my brother Boss,” It was Sans turn to fidget with his almost empty whiskey glass, which contained only melted ice at this point. Suddenly he wished that he had also gotten another round when Muffet had refilled the taller monster’s glass. “I work for him. As part of the Royal Guard.” The other Papyrus didn’t make any interruptions as Sans continued.

“But that’s not it. The collar…” Sans’ throat had never felt drier- if that was even possible for a skeleton who technically didn’t even have a throat. “The collar is a sign. A… mark, if you will.”

“A mark… for what?” The skeleton sounded as if Sans’ response could utterly destroy him.

“A mark that I’m… my brother’s property,” There was little to no way to dance around the topic. “He owns me. He really is my boss… because he’s free to use, and abuse me… in whatever way he pleases.”

Silence was Sans’ only response.

 _That was a mistake,_ Sans knew it was true. _A huge goddamn fucking mistake._ What the hell had Sans been thinking? He hadn’t been- of course. He never thought before opening his stupid mouth, which only got him into more and more trouble and made everything exponentially worse.

 _I shouldn’t have told him. I could’ve lied. I could’ve said literally anything else. I could’ve said nothing at all._ But instead he had allowed this skeleton to convince him to open up about the truth- the truth of the twisted, disgusting life he lived.

 _He probably thinks I’m disgusting. That I’m some sort of… broken whore._ Maybe he was even right. Sans knew that the other Papyrus would never do something so… _wrong_ with his own brother. Sans was sure the other monster wouldn’t ever be able to look at him the same way. And he didn’t blame him.

The moments after Sans’ confession seemed like an eternity to the skeleton. In that seemingly infinite sum of time, all the skeleton could do was wonder just how the other monster would react. Would his disgust for the monster turn to anger, or pity? Or would it just simply remain as disgust of Sans’ actions, revolting and vile? He didn’t know this monster all too well, after just an hour or so talk with him. He was hardly sure how he would take the reveal.

What Sans hadn’t been expecting was sobbing.

Beside him, the other Papyrus choked back tears. And it was now Sans turn to be surprised by the other’s outburst. Why would what Sans had said cause him to cry? Sans had gotten that the skeleton was getting upset about his brother, who had assumedly been moved from his universe just like Sans himself had been, but why would this be the thing that tipped the skeleton over the edge? None of it even affected him in any way at-

 _Oh._ The moment the realization hit Sans, it made him feel like a fucking idiot.

_His brother._

If he had disappeared from his universe only to appear here… then that meant the Sans who had been in this universe had disappeared from this universe to appear in his native one. They’d swapped places. Sans had moved from the hellhole that was his Underground to here- where it was warmer and the people were nicer and everything was brighter. And the other Sans- the one who couldn’t even handle sugar or caffeine…

Sans didn’t need to complete the thought to realize just what the problem was. This other universe’s version of him could hardly handle those things. What were the chances of him being capable of handling a universe of killers and violent murderers? Or having a sick and perverted version of his brother trying to fuck him with collars and leashes?

An innocent and kind version of Sans would have no idea what he could possibly do in a universe where kindness was stepped on- grinded to a pulp under the mighty boot of those power-hungry individuals, eager to enhance their own strength with another kill.

Which meant Sans had to be the fucking stupidest person in the universe- in both universes. Not to mention an asshole. He hadn't been meaning to make this Papyrus cry. He didn't want to see this Papyrus cry. He had been really nice to Sans this entire time, even though the shorter skeleton’s presence here had royally fucked up everything. He was just too stupid to make the connection before.

Yet all Sans had done since arriving here was cement the truth of how ruthless and uninhabitable his Underground was for monsters like the ones in this universe. He’s explained just how ugly and violent life there was, with murderers and backstabbers lurking in every corner. How even his own brother abused him and used him to his will, stepping all over him in the process.

 _Well, they probably wouldn't even last a day._ The other monster’s previous question made so much more sense now. But Sans’ reply couldn’t possibly have made things any better. If he had just realized sooner, then perhaps he could’ve softened the blow. But the statement was now ringing through his skull, mocking him as it made Sans only blame himself more. Only he could manage to so badly fuck up.

"Thanks," The Papyrus stood up from his stool without warning. The tears were still streaming down his face, but he was making a conscious effort to silence them now. Sans could feel the eyes of every monster in the bar on them, and he felt his guilt crawl down his spine. "For the honesty, at least."

"Wait!" The skeleton was out of his own stool as he called out the word, following the upset monster. He had messed this up, so he needed to fix this. This had been the first monster in forever who had treated him kindly and tried to comfort him, and all Sans had done in return was confirm what was most likely the other’s worst fears.

The door to outside the bar flung open, pushed by the larger monster. It closed behind him for a split second before being shoved open by the smaller skeleton.

He found himself back out in Snowdin. The soles of his red sneakers met with the familiar crunch of white snow underneath as his desperate dash out of the bar came to a halt. The skeleton’s white skull pivoted frantically as red eyes scanned the area of the town. With a bright colored hoodie like his, Sans was sure he would’ve been able to see him. But there was no skeleton to be seen.

Instead, Sans stood in the doorway to Muffet’s- an alternate universe’s version of the shitty bar he ate at- in a different version of his town, different from the regular one in every single way- in a completely separate universe from Sans’ home.

And the skeleton had just lost what had been his only guide.

**Notes for the Chapter:**

> ~Edited 4/15/17~  
> I'm currently in the middle of editing most of this story.  
> Hope you still enjoy!


	3. Chapter 3

With unreal speed, the menacing monster crossed the living room to where Sans was standing. Before the smaller skeleton could even react, the back of his spine slammed hard against the wall behind him. A strangled yelp escaped from Sans’ mouth- equally out of both pain and shock.

"Well, it seems like you certainly didn't get very far," A smirk formed on the skeleton's face as Sans was pushed harder against the wall. "Can't say I'm surprised. Even if you did leave, you'd still coming crawling back to  _me,_ " Sans remained silent- the speed at which the situation had so drastically turned had left him in the dust, the skeleton’s mind was still trying to process everything. It didn’t help that Sans didn't have the slightest idea of what this other skeleton was talking about. 

 _This must've all been some mistake._ Sans assured himself, as a worried smile made its way to his mouth. He could fix this. All he need to do was talk this out. He'd be fine. Surely there was a reasonable explanation for why this skeleton, who looked uncannily like Papy, was half naked with his discarded clothing strewn half hazardously across Sans’ living room floor. A very odd and specific explanation, yes, but a reasonable one nonetheless.

"What are you smiling about?" The monster growled, his hands unmoving from their spots on Sans' body. The forced smile fell from Sans' face as the monster's grip tightened on him even more. He could feel his bones begin to ache under the pressure. The larger monster looked over Sans. "What the hell are you wearing?" He demanded, scrutinizing Sans’ outfit.

The smaller skeleton opened his mouth to say something, yet the words were never allowed to come out. "It doesn't matter," The larger monster continued, ignoring him. "All that matters is that you're missing something very important."

 _I am?_ Sans eyes did a quick jump downwards, confirming the presence of his typical navy blue pants. However, the other monster wasn’t concerned with what the skeleton wore on his lower body. Sans felt the larger monster’s ungloved thumb trail down beneath his bandanna, scrapping against the exposed bone of Sans’ neck as it seemingly searched for something that could not be found.

"It seems someone doesn't have their collar,” The larger skeleton sounded disappointed as he scolded Sans- but Sans was hardly concerned about the other monster’s tone.

 _A… collar?_ Blue eyes widened in confusion. What was he talking about? The urge to escape from the other monster’s grasp was growing stronger. Not that Sans particularly liked it in the first place, but something was beginning to make his nonexistent skin crawl with the realization that he might have a much more difficult time talking his way out of this situation than he had hoped.

 _"Tsk, tsk, tsk,"_ The larger monster made the noise, conveying his displeasure further. "I would've hoped you had learned your lesson. Especially after last time."  _Last time?_

"What are you talking about?" Sans finally was able to make his words come out, but it didn’t take long before he regretted his choice to do so. One moment he was pinned tight to the wall, and another he was on the ground, grasping his face as he recoiled from an attack that he had no recollection of ever receiving.

It wasn’t until moments after being flung to the ground, and his skull slamming down on the carpet floor below that Sans pieced together that he had been hit by the taller monster.

Sans could feel the scratch marks across his cheekbone, burning in pain. He inhaled sharply and lied on the floor motionless, stuck into stunned silence. He had been hit- hit hard. Hard enough to leave noticeable marks, Sans was sure. Hard enough that it had _hurt_. Whenever he had been hit before, it had been during training with Alphys or a sparring match with a monster. It had never been out of the blue, without warning. Why was it that it seemed so much more painful when he didn't know it was coming?

The question raced through Sans mind as his hand reached up to touch the scratches. They were sore, cutting through the outer layer of his skull.  _I don't think anyone's ever hit me that hard before._ Even Alphys' attacks didn't hurt that much. That thought was a troubling one, because the mighty warrior was one of the strongest monsters Sans knew.

"Get up," Long, bony fingers wrapped around his neck, pulling him up easily and placing him once again up against the hard surface. "I didn't recall allowing you to speak," Sans kept his mouth shut this time- partly out of fear, and partly because of the shock he was left with after being hit. The monster holding him smirked wickedly. "Good. That's much better, though... I'm afraid I still have to punish you for leaving me this morning... and the collar, of course."

Panic immediately arose in his chest. _Punish?_ Sans knew he didn't like the sound of that. This monster… he wasn't like other monsters Sans knew. He was brutal. He had attacked him. In Sans’ own house. And while he may have looked like his brother, he certainly wasn't kind or caring at all... in fact, he was the opposite of that.

The monster had already shown he wasn’t against hurting Sans. It didn’t take Sans too much work to figure out that the punishing the monster talked of meant he was far from done hurting the skeleton.

 _Did this monster hurt Papy too?_ Worry quickly overtook Sans’ thoughts. Is that why Sans had woken up alone? Yet… Papy was much stronger than Sans. Surely, Sans’ bro could defeat this other skeleton… couldn’t he? Or was this monster too much of a match even for him? Sans thought Pap could handle anything thrown at him…

 _Stay calm, stay calm..._ Sans told himself, but it wasn't helping. Panic was still building up inside him. One thought raced onwards to another in his mind, until the only thing he was certain of was that he needed to get help- that he had to get someone. Anyone. The monsters in town, Muffet, Alphys, or even Undyne- despite the fact she was all the way over in Hotland. They would all know what to do. Yet he was stuck here, trapped. He needed to break free. Only then could he get the help he needed. That much was obvious.

 _Alright..._ He tried to recall his training with Alphys, but the soul beating inside his chest, threatening to burst right out, made the task no easy one.  _Just stay calm... and try your hardest!_ Alphys always said if he managed to do that, everything would turn out alright.

Sans could sense the other monster gathering magic, readying an attack. He too began to do the same, planning to summon some bones. _Maybe I could scare him off,_ Sans hoped. That way he wouldn't have to hurt anyone.  _A few bones ought to do it._ The problem was, being in such close quarters prevented Sans from doing any maneuvering or dodging. And if he was hit by a single attack…

 _Don’t think like that._ Sans told himself. _I’ll be fine._ He’d make it through this. He just had to remember what Alphys had taught him in their training sessions.

The other monster was faster than Sans; he was able to gather his magic first, the energy pooling inside the skeleton's skull. Sans’ panic willed his body to struggle in the other’s grasp. He needed to break free. He had to be able to dodge this other monster’s attack. Failure was not an option, but unfortunately, the strength of Sans’ willpower alone was no match for the steel grip of the other’s actual strength. The skeleton was stuck helpless as the larger skeleton’s jaw opened wide, and magic poured out.

If it had been an actual attack, Sans would’ve been done for. He was pinned, with nowhere to run or dodge and not even a chance of the other’s attack missing at such point-blank distance. Though luckily enough, it seems as if the larger monster had been pooling his energy for something… else.

A lapse in the skeleton’s concertation, caused by his uncertainty, ended Sans’ efforts to form a counterattack. The other monster’s attack hardly seemed to be of such nature. From his mouth emerged a long red muscle. A tongue- red and slimy and something Sans had never seen on a skeleton before. But sure enough, the glowing, magical organ hung before the other monster’s jaw, inches from the smaller skeleton’s face.

Without warning, Sans felt his feet lose their place on the floor beneath him- the last bit of leverage the skeleton had to break free. The back of his gray armor scratched against the wall as the skeleton was lifted into the air and left with dangling legs, his skull more or less level with the other monster’s. Now, he was truly left defenseless against any attacks the other monster might wish to make.

"What are you- _Mhmm!_ ” Sans was silenced as the larger skeleton forced the tongue into his mouth, the rest of his statement muffled in his surprise. The skeleton’s cheeks involuntarily flushed a bright blue as the slimy organ danced around the inside of his mouth. Once again, Sans was stunned into wordless inaction.

The whole exchange felt… weird. Not… _gross_ weird, like how Sans would’ve predicted by just looking at the wet, red organ. Yet the feeling of the tongue dancing through the hollowness of his uninhabited mouth made it none too pleasant, either. It was just… weird. And uncomfortable.

Despite the fact that Sans had no idea what was going on, two compulsive feelings began to emerge inside of him. One told the skeleton that this… _interaction_ was wrong in ways that Sans couldn’t even imagine… and another that told him that he was supposed to be doing something to make the situation less weird. Which was absurd, because Sans didn’t even understand what this whole thing was, never mind what he was supposed to be doing.

 _At least... it doesn't hurt_. Sans thought, focusing on the positive. The taller monster was pushing forward more, his tongue going deeper into Sans' mouth, until both skeletons' teeth met together in an audible clank. Sans had still been unable to downplay the weirdness of it. Or maybe weird wasn’t the right word for it. It didn’t feel strange as much as it just felt _different._ Sans had never experienced anything like this before. The insides of his mouth were wet, coated with saliva from the red muscle. What was this skeleton doing with his tongue?

 _What exactly was going on?_ Confused blue pupils stared questioningly at the larger skeleton, whose face was positioned less than an inch from Sans’. The taller monster’s eyes were closed, his concentration seemingly focused on… _whatever_ this was. Seconds later, the skeleton pulled away, red eyes burning above a devilish smile.

It was only when the saliva coated muscle dipped back into Sans’ mouth that the skeleton noticed the pool of magic forming by the other skeleton’s pelvis. Something hard was grinding against the bottom of the skeleton’s hip bone. Something that made Sans increasingly grateful that the only item the other skeleton was wearing happened to be pants.

Blue eyes opened wide as realization finally presented itself in Sans’ mind. The tongue had thrown him for a loop, but he wasn’t completely naïve. The skeleton knew what that hard lump pressing beneath him was; Papy had sat him down and had the uncomfortable talk associated with it a long time ago. Too be truthful, Sans still was pretty unfamiliar with the topic… but if this was happening to him, right now…

Sans gulped.

The warning bells in Sans’ head were on full alarm. It didn’t take long until his indecision was kicked from of his mind once he understood the gravity of the situation. Sans started to push hard against the skeleton in front of him, panicking to rid himself of the tight grip that encased him. The monster’s grasp seemed to tighten in response. The two hands squeezed around the bones of Sans’ wrists, unwilling to lessen their hold in the slightest.

Sans’ insides were on fire. There was another feeling filling his soul- another sensation the young skeleton wasn't familiar with- but he ignored it, pushing it down and instead allowing the sense of urgency to rise. Sans fought harder against the hold, desperate to escape. The other skeleton was moving the wrists above Sans’ head together, so he could keep his grasp on them with just one hand. The iron grip hardly seemed to lessen with just one hand.

Sans could sense the second hand, moving along his left side as it reached toward Sans’ bottom to tug down his blue pants. He could feel the clothing begin to slip- one of the few layers between himself and the undesirable organ the other skeleton was grinding against his pelvis. Sans was not eager about this development.

In a last-ditch effort, the skeleton bit down hard on the foreign tongue in his mouth. And while that did stall the larger monster’s plans for a short while, it also managed to make him much angrier.

The skeleton pulled away in a hurry, hissing in pain, but Sans’ wrists remained pinned, the skeleton still dangling helplessly like a victim hanging from the edge of a cliffside. As the larger monster moved back, Sans felt saliva trail out of his mouth from the other monster's tongue.

Pain raked through Sans’ side, his battle body shielding little of the other monster’s punch. The shorter skeleton wheezed violently, feeling effects of the physical attack even after the initial blow.

The menacing monster glared straight through Sans, "I’m going to make sure this is  _especially_ painful for you." The grinding sensation returned only seconds later, but the larger skeleton now seemed even more determined to strip down Sans. He was shaking now- in terror as well as pain. Sans didn’t want… this. But he was so scared that he might not have a choice in the matter.

It was in the midst of the fear that another idea formed in Sans’ head. The smaller skeleton swung his legs up from where they were hanging and planted them on the monster's rib cage, kicking hard to shove the skeleton away. Maybe it was because the power of Sans’ legs was more than the strength in the larger skeleton’s upper body, or maybe because the skeleton had managed to catch the other off-guard, but his plan miraculously worked.

It wasn't much, but the other monster stumbled back a step or two, dropping Sans to the ground. The shorter skeleton caught himself on one knee, and a sigh of relief escaped from his mouth. Sans knew he wasn't safe yet, but the feeling of the hard member grinding against him was gone, and he couldn't help but be relieved.

"What the heck are you doing!?" Sans demanded.  _What kind of monster just shows up in someone else's house and tries to- to- do things to them?_ Sans could feel his cheeks still burning, tinted a fierce blue. The pain from the two earlier hits was still present, but it was dulled in the back of the skeleton’s mind, forgotten and abandoned for now. Sans’ current focus was on what had just nearly occurred- and might still.

The larger skeleton paid no heed to the question. "You little fucking cunt!” He shouted, furious. The foul language he used was the worst Sans had ever heard. “You’re really gonna get it now!” The skeleton launched forward at Sans once more, yet this time, the shorter skeleton was ready.

Sans ducked under the larger skeleton's arms, hoping to send him crashing into the wall. Instead, the monster was able to catch himself, slamming a hand against the wall. He quickly turned to face Sans, a snarl on his face.

"If you want to play like that, I'll play like that!" The other skeleton growled back, beginning to pool magic for an attack that Sans knew wouldn't be as harmless as a tongue. "Just don't say I didn't warn you, you little bitch.”

Sans formed fists from his gloved hands. His ragged breathing wasn’t from any physical strain- it was caused instead by anger. Stirred by rage, building up inside him and fighting to take over the skeleton’s mind and explode.

 _How- how dare this- this pervert try to do that!_ Sans could still feel the color on his cheeks. He could still remember of the unwelcome magical organ, pressing against his pelvis, trying to get… inside of him. _What kind of monster did something so… so… so repulsive?_

"Who the _hell_ are you!?" He burst out loudly- so loudly that the other skeleton couldn’t possibly ignore him. Both skeletons froze for a second after the outburst. Sans’s hand instinctively moved upward to cover his mouth. He really hadn't meant to swear, it had just sort of slipped out.

"What the fuck do you mean, who am I?" On the other hand, the larger skeleton seemed to have no problem using that type of language himself.

"I don’t even know who you are. And you’re trying to… to…" _Rape me._ Sans couldn’t bring himself to say the words aloud, yet the other skeleton seemed to catch on.

The larger skeleton began to step forward, the confusion on his face fading away and replacing itself with an eerie smile. Sans quickly prepared himself to make an attack. He didn't like resorting to violence, but he didn't see much of choice. If the larger monster lurched at him again, or tried to summon his own magic… or tried to do what he had before again, then Sans would be ready.

Thankfully, the taller monster stopped right before Sans, and didn’t come an inch closer. "Why, what do you mean, my pet? I'm your Boss, the one and only."

"I've never seen you before in my life," Sans wasn't buying any of this.  _Pet? Boss?_ Was this monster crazy?  _Do I look like a pet?_

"Now don't be ridiculous Sans, how could you forget me, your dear brother?"

 _No._ Sans refused to believe it for a second. This certainly wasn't Papy. He batted away the bony hand that reached out to touch him. He could feel tears build up in his blue eyes. _Why am I crying?_ This monster was obviously lying to him. He was some sort of imposter. _So why am I crying?_ Big skeletons didn’t cry.

“You… you really don’t recognize me?” The tone of the second monster seemed to break into something that sounded close to worry. Worry that was actual, sincere and honest concern. But when the larger monster stretched out another hand, more forceful than his previous one, to grab Sans by the hip, the skeleton was convinced it was just a ploy.

Sans didn’t hesitate another instant before summoning the magic he had pooled together to defend himself. Without any warning, a bright blue cage of bones encompassed the monster in front of him, leaving him trapped inside.

"What the-" The monster's arm shot back in surprise the moment it touched one of the blue bones, startling the skeleton as he took damage from it. Sans wasn’t there to hear the end of his shout. The little skeleton was already flying out the door. He knew he needed to get help. Sans knew he needed to get the real Papy.

* * *

The familiar sounds of snow, crunching underfoot as Sans raced toward the center of the familiar town of Snowdin was music to the young monster’s ears. It was his first real moment of safety ever since he had encountered the larger monster back in his home.

No way was that monster in there his brother. It wasn't possible. Pap would never attack him. He would never try to- try to- _Rape him._ Sans was disgusted by the mere thought of it. Just the idea of it was so... gross. So unjustifiably awful.

His brother  _did_ swear, that was true, but it was almost always under his breath or to himself. Never was he so openly vulgar. And, if by chance he ever did say anything like that, he would immediately apologize.

His Papyrus wore orange hoodies and told bad jokes. He smoked and drank honey by the bottle. He was lazy and hated getting up early. That monster in there was not any of those things.

 _Why am I still trying to convince myself of this?_ Sans knew that the monster inside his home hadn’t been Papy. That was indisputable, despite whatever the other monster had claimed. Sans was well aware of that truth. So, instead of arguing with himself, he should instead be focusing on the task ahead of him- finding help.

 _"Oof!"_  Sans soon regretted not paying as much attention to his surroundings as he did to his own thoughts. He had been completely unaware of the other monster until they’d collided, and Sans was flung into the snow. “My bad,” The skeleton quickly apologized as he pushed himself up to face the other monster.

"Yeah, it was," The monster was a lot larger than Sans expected. Bulkier, too. For a second, Sans almost thought he recognized him as one of the regulars in Snowdin. But his black jacket and imposing demeanor were unfamiliar to the skeleton. “Watch where you’re going, you runt.”

Sans watched as the monster walked away, hardly giving him a second glance. _That was… a little bit much._ He thought, turning away. All he had done was run into him, and no real harm had come of the encounter. Plus, Sans really hadn't meant to. It had been an accident. Yet none of that seemed to matter to the larger monster.

The short skeleton let himself fall back into the snow. _Today is not my day._ Sans thought miserably, the wave of despair he had been holding back finally rolling over him. This morning had undoubtedly been one of the very worst in his life, and he still hadn’t figured out what he was going to do to solve it. The skeleton was scared of that monster that was sitting in his home, trapped. He didn't want to go back there. At least, not alone.

 _Muffet can help._ Sans told himself, knowing he was barely far at all from the spider's bakery and bar. He didn't really know the purple spider much, excluding the casual exchanges they shared whenever he picked Papy up from the bar when it was getting too late. But she was nice. The spider gave him baked sweets a lot of the time, too, which definitely didn’t harm Sans’ opinion of her. Muffet could probably help him figure out what to do. Plus, with the amount of time she spent with Papy, she might’ve even had an idea of where he had gone.

 _Or I could go to Alphys._ Sans was much more familiar with the leader of the Royal Guard. She would be glad to capture any monster pretending to be Papy. She could maybe even get some answers out of him.

Sans sighed. He didn’t like having to make hard decisions, especially in difficult situations like this. Thankfully, he didn't have to, as he was quickly swayed to his final choice as a stinging feeling began to spread over his bones.  _Cold._ The realization shot to the forefront of the monster’s mind, forcing him out of the freezing snow the moment he discovered the bitter cold temperature of it. In fact, everything was cold- much, much colder than Snowdin usually was.

Sans hugged himself tight with arms that provided little heat to his body, being coated in the snow. He could both feel and hear the chattering of his teeth. Quickly he shook the snow off of him, the frozen white flakes still clinging to his bones. Even after removing the icy crystals, his body still protested against the freezing temperatures. His battle body seemed to be no match for the cold.

 _Muffet it is._ Sans decided. No way was he crossing Snowdin to get to Waterfall like this. He’d freeze! …Or more likely, catch a dreaded cold. Which could end up being just as deadly. The skeleton craned his neck up so he could look around the town.

"Whoa," The town square was empty- which was unusual. Despite Snowdin seeming like a small, sleepy town, the center of town was typically quite lively. Usually monsters would be gathering outside now, in order to talk among themselves. But not a single monster was outside and about in the town. Even the monster he had just ran into was gone, having made a hasty exit. _Alright._ The skeleton turned toward the bar, beginning to walk towards the building.

It didn’t take long to notice that Muffet's looked like it was in worse quality than it had ever been. The potted plants outside the bar had all shriveled up and died. The bright lights didn't shine out through the windows, lighting up Snowdin like they typically did. In fact, one of the windows was even broken. How had the place fallen into such disrepair?

Sans’ speed began to stall as the skeleton began to pick up on more oddities. Like how the entire building was a different color- outside bricks being brown rather than purple. Or how the smell, wafting from out the broken window, was reminiscent of cheap, fried food, as opposed to the sweet pastries one would expect from a bakery. Sans’ blue boots dug into the snow as the skeleton came to a complete halt, seeing the sign on the bar.

 _Grillby’s._ Dark orange letters spelled out a name unfamiliar to Sans. The unfamiliar name was painted over the top of the building, directly above the doorway. _Grillby’s._ Not Muffet’s, like it should’ve been- like it always was. _Grillby’s._

 _It didn't just look different,_ Sans realized. It was a completely separate building than the bar he was searching for. A completely different building, in the middle of Snowdin, taking the place of Muffet’s. Sans knew that “Grillby’s” stood exactly where the bakery and bar had always been, ever since Papy and he had started living in the town. _But… that didn’t make any sense._ That couldn’t have made any sense.

Sans could hear noise, coming from inside the building. Loud and rowdy sounds, like rumbling laughter and angry yelling. Cautiously, the skeleton crept beside the broken window. He didn’t know what he expected when he glanced inside, peeking through the hole in the glass.

Grillby’s turned out to be a bar. A bar with a layout almost exactly like that in Muffet’s. Stools and booths and tables were all in the same spots. The jukebox and bar counter seemed positioned in a faithful recreation of the bar that usually sat in Snowdin. And sure, it was all different colors, and in a much worse condition than Sans had ever seen Muffet’s in, but the likeness of it was certainly no coincidence. How could it be?

The large table where the Royal Guards always sat in Muffet's sat completely empty- which made sense, seeing as how most of the Guard would be at their posts at this hour. Sans had a post he should’ve been at as well- but his hands were already a bit full with trying to piece together the solution to his current problem.

 _No Papy._ It didn’t take long for Sans to scan the room and notice the lack of a certain orange hoodie. Nor was there any purple spider present, either. She was instead replaced over by who appeared to be some sort of purple fire monster- Grillby, Sans assumed from the sign outdoors. With neither of the monsters Sans was searching for being present, it was clear that it was pointless to stay there any longer.

Sans slowly pulled himself away from the window. It was paradoxical how his head felt heavy despite the dramatic lack of understanding in his mind. The questions, swirling around his skull, certainly didn’t help the feeling.

 _What’s going on here?_ Sans turned away from the bar, only to reveal his eyes to the rest of Snowdin. His soul skipped a beat as his suspicions were confirmed. All of the building seemed to have changed, just like Muffet’s transformation to Grillby’s. The Inn, the shop, the houses... all of them were so different. The lights that usually burned in each of the windows of all the building were gone, replaced only with darkness. Houses were painted in darker shades. The library was even boarded up. All of it was so...

 _...unwelcoming._ Sans glanced around worriedly.  _Where was he?_ This twisted distortion couldn't possibly be Snowdin, could it?

Even the tree in the center of town, one of the things that shined the brightest in Snowdin, was dead. There were no lights or ornaments decorating it. No presents beneath it. The normal hustle and bustle of the town was gone. In its place was the stagnant sound of silence.

No, this couldn’t be Snowdin. Just like how the monster sitting in his living room couldn’t be Papyrus. None of this was right. None of this was normal. It was almost as if everything had changed overnight. Somehow, everything had suddenly swapped to being so _wrong._ And Sans had no idea why.

None of this felt real. None of this made sense being real. Sans had never met a monster who would try to force themselves upon another like that before. He highly doubted any monster in the whole of the Underground would willingly do something do horrible. But it had just happened, hadn’t it? Somehow, what had once seemed impossible had shifted to becoming a reality. But how could something like that be real, in _any_ sense of reality?

No, that couldn’t be real. It was something so awful- so unspeakable- that Sans was sure it couldn’t ever happen. Something so terrible had no right to be real.

Never mind the fact that _none_ of this made any sense, at all. Why would everything flip like this? The entirety of Snowdin and all of the residents in it- altered without warning. Without reason. That scenario was the sort of thing dreamed up by children with overactive imaginations and no understanding of how the world- _Wait._

 _Is this… a dream?_ The thought struck Sans and he almost feeling ridiculous for not seeing it sooner. The longer he toyed with the notion in his mind, the more plausible it seemed. This whole experience had every characteristic of a terrible nightmare, and he _had_ eaten awfully close to bed time last night. Papy and him should’ve eaten their tacos before they watched the movie, like they usually did. It was Sans’ lack of foresight that led to all this. Pap always said that eating right before he went to sleep would lead to nightmares.

 _Alright, alright..._ It shouldn’t be too hard to wake himself, right? _Just relax._ Sans paused in the center of the warped version of Snowdin his mind had created.  _I'm dreaming, and I’m fully aware that I’m dreaming. So when I open my eyes, I'll be back on the couch._  Papy's arm would be held tight around him, keeping him safe. In fact, if he concentrated hard enough, he could just about feel the warm embrace of his brother, and the sweet and smokey smell of his hoodie, smothering him as he slept.

Slowly, Sans' eyes peeled opened. The skeleton fully expected to see the orange hoodie his brother loved stuffed in his face as his big brother held him close. He was fully prepared to go back to his life, and start his daily routine before heading out to his post.

But there was no such luck. Still he remained in the center of the cold and dark Snowdin. He was still freezing his bones off. He was still alone.

Sans shut his eyes tight again. _When I open my eyes, I’ll wake up from this deranged dream. Pap and I will have breakfast, maybe I’ll make pancakes. If we’re out of pancake mix, then we’ll have cereal. Or even oat sludge, if we have to._ Sans never thought he’d be looking forward to the possibility of eating oatmeal again. _Then we’ll go to our posts, just like we do every other day. Because today is just like every other day._ Sans would check over all the puzzles and make sure everything was in order. Maybe, if he had enough time, he would even rearrange one of them into something completely different. If he was really lucky, a human might even show up!

Sans’ eyes opened again. The twisted version of his snowy hometown was still there. Quickly he shut them again, as if looking at it for too long might just make it real, and not just a horrid night terror concocted by his wild imagination in the dead of the night. His closed eyes felt wet, with unwanted teardrops forming around his blue pupils.

 _I'm not focusing hard enough!_ That had to be it. He needed to concentrate on the feeling of his older brother being there, cutting through the cold of this desolate Snowdin. His brother’s bright presence would burn through this bleak reality- this bleak fantasy. Sans was convinced he could feel it, the warmth of his big bro’s over worn hoodie and protective hold coursing through his entire body. The feeling of his soft breaths, blowing easily against the back of the smaller skeleton’s neck. He knew it was there, because the bitter cold was disappearing, and all that remained was the warmth.

Blue eyes opened, and the warmness quickly faded away to bitter cold. Still, he remained.

Again, he tried. And again. Neither desperate attempt produced results any more favorable than his first.

Slowly, the skeleton had to acknowledge the harsh truth that part of him had known since the beginning. He wasn't dreaming. It was stupid to even think that that might be the case. This was real, all of it. This changed Snowdin. The skeleton that claimed to be his brother, sitting in his house right now. The overpowering feeling of dread that was hanging over him.

The cold crept down the monster's spine, chilling him to the bone once again. The freezing temperature made his fingers feel numb, even beneath the usually warm shelter of his blue gloves.  _If this really is real..._ Which it was, Sans knew. _Then what am I supposed to do? What can I do?_

Sans had no answer for his questions. This would usually be the part where Pap took him by the hand and told him everything would be okay. Papy would do that lazy smile of his and Sans' uncertainty would melt right away. The older skeleton would crack a bad joke or two and lighten the mood. If Sans got tired, the skeleton would pick him up and let him ride on his back as he carried on, moving forward.

And then? His brother would find a way to fix everything. It always seemed like that was what Papy was able to do best. For how lazy and unmotivated the skeleton was usually, and for how much Sans had to yell at him to do his job and guard his post, he had always been the one who made everything okay. He was always the one who solved everything. He was always able to do things that never ceased to astound the younger skeleton. Papy would fix everything, and then life would go on as it did. Pap was always there for his younger brother, and he seemingly always had the solution to every problem.

 _But he’s not here now._ His disappearance was one of the increasingly many problems Sans needed to solve. _He can’t help me with this… because I’m all alone._ The first few tears began to fall despite the skeleton’s restraint, hitting the hard snow on the ground. It didn’t sound right in his mind. Each word made sense individually, but put in that specific order- made into that single phrase- it couldn’t register in Sans’ mind. It just seemed like a jumble of letters and a butchering of different sounds the felt like they should mean something to the skeleton but didn’t.

 _Papy's not going to be able to help me._ The idea was a strange one- especially when the Sans’ bro had been helping him through everything all his life. With every tough problem and choice, Papy had the other skeleton’s back. Except for now.

 _I'm on my own._ Sans choked back a sob as the reality of the situation began to sink in. _I’m on my own._ The phrase was beginning to make more and more sense in the skeleton’s mind, but that didn’t mean he wanted it to.

 _I’m on my own I’m on my own I’m on my own._ Wet streams formed down each of Sans' cheeks. For the very first time, the skeleton felt truly alone. For the very first time, the skeleton _was_ truly alone.

Sans didn’t like being alone.

 _I can't do this._ Sans was wheezing for air, sobs coming out between each inhale. There was panic filling his soul, pooling together for a different type of attack- one that didn't require magic. _I can't do this I can’t do this I can't do this._

There was no Papy to save him, like there always was. The only Papyrus Sans had seen had been an abusive rapist. And Muffet was also gone. If the skeleton went to Alphys, what’s to say the same wouldn’t hold true for her? Or even Undyne? What if they were all gone? Or worse, changed like his brother had been?

He… he didn’t know what was going on. Sans wasn’t going to pretend to understand. But what he did need to know was how he was supposed to solve any of this. How was he supposed the right the wrongs he hardly comprehended? It didn’t even seem like it could be fixed. It seemed like he was stuck in an unsolvable maze, trapped in a problem with no solution. So rather than just crying, the skeleton did the very next thing that came naturally to him.

Blue boots began to blindly kick through the undisturbed snow resting on the ground as the small skeleton surged forward in a random direction, spurred on only by the feeling of his mind tugging him in a direction away from this whole mess. His first steps began as a stumble, unbalanced and rushed- the only thing holding any importance to the skeleton in that very moment being getting far from the _wrongness_ of this Snowdin. It didn’t take long before he was running as fast as he could, his tears flying behind him.

* * *

Everyone always told Sans that running away from his problems never solved anything. It was one of those pieces of wisdom that everyone seemed to throw around carelessly- a bit of unquestioned knowledge that monsters were imparted with from a young age.

Maybe they were right. All of them; Papy, Alphys, and every other monsters who’d ever thrown that advice to Sans. Yet there was something undeniably liberating in the act of turning tail from the scariest problems of life and just running. Running away, with no destination in particular, and each footfall landing in a seemingly random place leading the skeleton down a different path.

The journey Sans’ feet took seemed completely chaotic and unplanned, but his mind guided him through the snow-coated forest in just one direction- away. Away from the skeleton who wanted to hurt him. Away from the town that wasn’t what it should’ve been. Away from Sans’ problems, that he didn’t have the slightest idea how to deal with.

The skeleton could feel the cuts and scrapes, collecting all along the exposed bones of his body as jagged ends of tree branches hit him as he ran. Sans didn't slow down in the slightest. He felt numb- numb to the minor pain that came with each new injury and unfazed by the cold, biting through his battle body. All he could focus on was each stride, carrying him in the only direction that seemed pleasant. Sans was determined to get so far from that place that he'd never have to see it again.

He could feel a tearing sound as his pants snagged on something and caught. Without a moment of hesitation Sans pulled his leg hard, the clothing being torn as he did so. Yet he didn't care. That hardly mattered now. 

He had nearly been raped today. Molested by a skeleton that looked just like his own brother. And it had been terrifying. He had no control to stop it from happening. Luck may have been the only reason he had escaped.

Sans had never had… _that_. He got flustered just thinking about it. The skeleton hardly ever thought about… stuff like that. And he had certainly never pictured himself having it. He never wanted to have been touched like that. To be raped. It was disgusting. It was _wrong._

...But it had nearly happened. And he’d been powerless to stop it until it was almost too late.

 _Shut up,_ Sans told himself, pushing any thoughts of this morning far, far out of his mind. All he needed to focus on was the urge to keep running, pulsing through the skeleton’s soul. The urge that he was acting upon without restraint, because he saw no reason to ignore it.

Blue boots kept an even pace, plowing through the snow as if it was nothing but air. He felt as if his mind was being pulled, and each step was being unconsciously guided to land in a specific direction without any sort idea why. It wasn’t until the heavily populated forestry faded into a more sparsely concentrated area of trees that the skeleton allowed his pace to lax in even the slightest.

Those many trees thinned into fewer and fewer, until the skeleton reached a clearing, somewhere in the middle of the Snowdin forest. It was then that the weariness caused by his unrelenting sprint and the ache of his legs caught up with him. Sans had hardly felt tired at all when he had been running, yet now it all seemed to hit him at once. His soul was pounding away, though the panic seemed to have been forgotten, tossed away as the skeleton ran from any sign of trouble.

The clearing surrounded a small, frozen lake, and a large tree hung over the icy surface. A tree perfect for collapsing beneath, Sans’ body decided, as legs gave way unceremoniously, dropping the skeleton to the snowy ground by the tree’s trunk. The snow was just as cold as it had been in Snowdin, but Sans’ aching body could hardly care.

 _Breathe._ He told himself, not only to reclaim the air he had lost from the long run, but to calm his emotions. The knot in his soul seemed to untie with each breath inward and each exhale outward.

 _There you go, bro._ He could almost imagine Pap's hand on his shoulder, comforting him as the crying ended. Yet he knew it wasn't there.

 _I should examine my surroundings._ That was what Alphys had taught him. Survival tactic number one. While it hardly seemed of any use to the skeleton, he did so anyway.

The clearing itself wasn't very big at all, maybe two or three times bigger than the living room to his house. Pine trees topped with snow surrounded the outskirts of the small area, where the clearing transformed back into dense woods. The snow here remained almost entirely undisturbed, like no one else came here. _Which meant a little peace and quiet to figure my thoughts out._

 _I should check myself over._ Alphys also said that the adrenaline running through his soul whenever things got intense often blocked out the pain of injuries the required the utmost attention. Bruised and broken bones could seem like nothing in the heat of the moment. The frozen lake in the center of the clearing had a sheet of blue, glassy ice on its surface, shiny enough to use as a mirror. On all fours, the skeleton crawled over to the ice, positioning himself over the lake. Sure enough, the frozen surface shined back with Sans’ reflection, yet for a brief moment, the skeleton was unable to recognize the monster staring back at him.

 _Woah._ Blue pinpricks met their own image in the lake mirror. The skeleton’s eyes were not starry eyed and filled with their usual excitement and joy. The regular flush of color beneath his eyes on his cheeks was gone as well.

Minor scrapes covered Sans’ skull, cuts he had won from tree branches during his mad dash. And five long marks, deeper than any other, raked across his cheekbone. They cut into the bone, exposing the pink and red marrow of its first inner layer. Those would certainly take a bit to heal completely. That was, if they didn’t scar.

The skeleton’s gaze trailed across the unfamiliar expression on his face. So often did Sans smile that it felt so very strange to see his mouth making the exact opposite of that. He knew he was a typically happy monster. He was always smiling, always beaming with excitement and bustling for each new adventure every day would bring.

When he found himself in situations where it was impossible to maintain that happiness, still Sans tried his best to smile. If not for himself, then to brighten up the days of all those around him. It was something he had learned from Pap, and his bro’s lazy grins that made everything seem okay.

Yet there was no smile on Sans’ face. There was no cheeky grin or small comfortingly expression. And it was no surprise. Because how was he supposed to be happy, or even pretend to be smiling with everything that had just happened to him? He couldn’t do that.

 _I have no idea what's going on..._   _and it’s all up to me to fix it._ How was ever supposed to accomplish that?

Clear droplets of liquid started to gather on top of the icy lake surface, falling from the skeleton’s eye sockets and covering his reflection. He was crying again. When had he started to cry?

A balled fist slammed into the skeleton’s impromptu mirror, hardly cracking the thick ice. _Why?_ He felt so hopeless and lost asking the question, knowing there was no way he’d ever receive an answer. _Why?_ The monster wiggled himself back under the tree, moving from four limbs to two. _Why was this happening?!_ Sans felt like screaming the question out, but he knew he still wouldn't find the answers he sought. _Why now? Why did this have to happen to me?_

The rush of his run was fading, and the skeleton was beginning to feel every scratch and cut stinging across his bones. The cold was settling on him, taking control of his body. It was twice as worse now, the tears in his armor exposing him to the freezing air even more. He was gonna freeze out here. And to be honest, a part of him was okay with that.

Another part of Sans knew he was being dumb. He could solve this. He just hadn't tried. There was a way to solve every problem. Sure, he didn't even understand what all this was yet, but it was evident it needed fixing. Everything was so... wrong. So out of place. So abnormal. If he tried hard enough, he could fix it all. Yet nothing was going to be fixed if he just continued to sit here, in the middle of Snowdin forest.

Sans knew he had to get up and start doing something to fix this, but he couldn't bring himself to stand up and return to his home, where one very messed up skeleton who claimed to be his brother resided. But... if he didn't do anything. Well. The skeleton wouldn't be held forever. At most, the cage would last a few hours. Sans could only use so much of his magic to sustain the attack.

Someone had to understand what had happened. Someone smart. Maybe the Undyne of this place could help. Sans hoped she hadn't changed too much in the twisted reality. He liked the dorky fish scientist. He never understood her science things, but if anyone could make sense of this conundrum, it was her.

 _Yeah!_ Sans eyes lit up just a tiny bit. He had a plan. That was like, halfway to solving the problem, right? He could feel his excited self beginning to return, at least partially. Despite the freezing temperature, he could feel the flush of color on his face begin to come back, warming his cheeks. The problems he had seemed to fade away in the back of the skeleton's mind. None of them mattered. Undyne could fix this all, and then he'd be back with Papy- the real Pap. Sans would be home and safe before he knew it.

That was the way to solve everything. The skeleton shot up. Sans knew didn't have a moment to waste. He had to get to Undyne's lab before anything else horrible happened in this place.  If Sans’ bro could see him now... Sans knew his brother would be proud. The skeleton was gonna do this. All by himself- and, well, with Undyne's help, too.

The skeleton had started wiping the freezing white powder off his torn clothing when he heard the first sound of trouble- rustling, behind the tree line surrounding the clearing. It sounded like movement, coming from the forest, and that thought alone gave Sans reason to pause. For a second he waited, unsure if his mind was playing tricks on him.

Maybe he wasn't as alone as he thought. The idea unnerved him. He could be being watched right now and he didn't know it. The urgency of carrying out his plan suddenly seemed much greater than it had only moments before.

Then the skeleton heard the same rustling of movement for a second time. It had definitely come from his left, the same direction back to the unwelcoming version of Snowdin. And it definitely hadn’t been the sound of tree branches, whooshing in the nonexistent wind. The skeleton felt himself lock up for a moment. Had someone followed him from the town?

"Well, that was a neat trick back there," Sans jumped at the newcomer's voice. Dread and fear replaced the positive feelings that had only just returned seconds before as he realized who the speaker was. "You had me going there for a second."

The panic returned, threatening to claim Sans once more. The owner of the familiar voice came out from behind a tree, only a dozen steps away from the smaller monster. Apparently, the larger skeleton could be deadly silent when he wanted to.

He was fully clothed now, the bones of his chest and the red soul sitting inside no longer visible to the smaller monster. He looked much more intimidating that way. The black spiked armor chest plate he wore, and the way how each individual finger of his red gloves seemed sharpened to a point, was completed by the frightening look of his expression, with razor sharp fangs and glowing red eyes and the deep scar across one of them, that Sans was surprised he hadn’t noticed back in the living room, when he had been inches away from the other monster’s face. It was all downright terrifying.

And it occurred to the skeleton that was _sort of the point._ Sans wondered how he had ever mistaken the larger skeleton’s armor set as anything similar to his own. The skeleton wore his battle body because it looked absolutely awesome, and would protect him in battle. Yet this monster’s armor was made to intimidate. To plant a feeling of unrelenting fear in the pits of monsters who stood against him.

 "A blue attack... I have to admit, I'm impressed," In a trancelike state, Sans began to move backwards as the larger skeleton crept towards him. Red boots and blue ones each crunched over the snow beneath them as the pair continued to move, the distance between them shortening with every step. Sans didn't know what to do. He knew he couldn't outrun this monster. He was still beat from the last dash he had just had. Plus, this monster’s legs were nearly twice the length of his own. The taller skeleton’s longer strides meant he would quickly overtake Sans.

 _How did he break free?_ The thought raced through Sans mind unanswered. The cage should have held him for longer than this.

"I was starting to think you had been training. Of course, that obviously wasn't the case,” The heel of Sans' boot pressed against the hard trunk of a tree. Eyes widened, scared. "Still as weak of an attack as ever. Still a wimpy one damage attack, isn't that right, Sans?" The smaller skeleton gulped. He was out of space. He could take off running, in a sprint, and try to catch the other monster in surprise, but… well, Sans could sense the magic the larger skeleton had pooled together already. If he turned and ran, it would hardly be much trouble for the larger skeleton to shoot a well-placed bone attack into Sans’ spine, and then… that would be it.

The menacing skeleton chuckled, ignoring the panic in Sans' eyes. "You know, I find it funny that of all the places you go to, you come here..." The monster glanced around the clearing, taking it all in for himself. "What, you don't think I didn't know about your little hiding spot?" Sans was getting used to the fact that most of what the monster said made no sense to him. The larger monster planted an arm above Sans' right shoulder. Their faces were inches away.

Sans knew the time for confrontation was now. He needed to summon another blue cage. However this monster had broken out of the first cage, it had still bought Sans some time. if Sans could summon another one, that could give him a decent enough head start to the lab.

"You've been very disobedient lately, haven't you?" Sans could sense the bigger skeleton summoning his magic in an attack that was growing more and more familiar to the shorter monster. "One would think that after so long, a pet would start listening to their master." This skeleton was not his brother, never mind his  _master._ Sans would never let himself be controlled by this evil monster.

"Unless, that is, you're starting to enjoy your punishments," The twisted incarnation of Papyrus opened his mouth, and Sans could see the slimy red muscle inside. "Which is just ironic, isn't it? For all the times you've called me a pervert, I never knew you were such masochist, Sans." The young skeleton had no idea what the word meant, but he knew from the other monster's smirk that followed the statement that it was nothing good.

"Well, since that appears to be the case, I'm happy to help," The larger monster pulled close to Sans, pushing the skeleton against the tree, trapping him.

Sans could feel the larger monster’s hands grab tightly to his hips. No amount of squirming could free himself. The tongue found entrance once more, and Sans could feel the fierce blush return to his cheeks.

No, he wasn't going to let himself get flustered. If he got flustered, then he wouldn't be able to stop the larger monster. Sans needed to stand firm.

"No-" His protest was made to no avail, muffled by the red organ forcing itself into Sans mouth. It didn’t take long before the grinding sensation was back as well.

“Oh come on,” The larger monster said, pulling back without warning. “You know you’re enjoying this.”

 _I don’t know what could be possibly giving him that idea._ Sans thought, fighting as the tongue came in once more, and the other monster’s second organ maneuvered itself to beneath Sans’ backside. But it was impossible for Sans to free himself this time. The larger skeleton was too close for his previous trick to work once more, and his grasp seemed exponentially tighter than before, as if he was only now using his full force.

“I find it funny, you know?” Sans couldn’t help be thankful when the larger monster pulled back, the sensation of the hard organ grinding against Sans’ lower region and the intrusion of his mouth both ceasing. “That even after this, you still haven’t revealed your dirty little secret.”

 _Secret?_ Sans’ eyes narrowed at the other in confusion. For not the first time, the skeleton didn’t have the slightest clue what the second monster was talking about.

A small, dark chuckle escaped the larger monster’s mouth, and both his summoned ecto-parts disappeared. Slowly, one of his gloved hands moved up Sans’ side, moving to the exposed region of his neck while the other stayed pinned to his hip.

“Yes, your little secret,” It was almost as if the skeleton could read the confusion in Sans’ expression. “I’m sure you know what I’m talking about,” The larger monster’s grin seemed almost predatorial.

“I- I don’t,” Sans replied honestly, partly terrified that he’d be slapped for speaking again.

“Oh?” Feigned surprise passed over the larger skeleton’s face. “Well then, would you care for me to share it with you?” Sans wasn’t sure he did, thinking about it, but the monster claiming to be his brother wasn’t waiting for his answer.

“Why, your little secret,” The hand on Sans’ neck suddenly tightened, wrapping around the vertebras. “Is that you’re not really Sans, are you?” The shorter skeleton’s soul skipped a beat as the expression on the menacing monster’s face shifted.

“No, no, you aren’t my brother,” A hand slowly released its grasp on Sans’ hip, but it hardly mattered, because he was still pinned to the tree by his neck, and he definitely wasn’t going to be able to get away. “After all, my brother would certainly recognize me, right? And my brother would never be so misbehaved as you- well…” The monster shook his head in thought, as if he was trying to decide something. “…he’d never be as _openly_ misbehaved.”

“Collarless, running away, disobeying my direct orders, and even attacking _me,_ ” The larger monster shook his head in disapproval as he listed the events like a collection of crimes Sans had committed. “It’s almost like you’re asking me to kill you.” A red bone pressed against the skeleton’s neck.

The larger monster pulled away his gloved hand from Sans’ neck, and instead let the glowing magical attack do all the work of pinning the skeleton motionlessly to the tree.

“So, I’ll ask this just once, and you better hope that I like the answer you give me,” Two cold, red eyes, absent of any sign of emotion or weakness, burnt into Sans’, and the short skeleton knew everything had taken a turn for the worse.

“Where is my brother?”

**Notes for the Chapter:**

> ~Edited 4/21/17~  
> As of right now, this story's going through a massive overhaul. If you want to wait until it's rewritten before you finish reading, I wouldn't blame you. Either way, I hope you still enjoy!


	4. Chapter 4

_Gone._ The skeleton’s spine slid down the brick wall as he slumped down to the snow coated ground. This alternative universe’s version of Boss was nowhere to be seen. And his disappearance was unquestionably Sans’ fault.

 _I… I should go after him._ That would be the nice thing to do. The “right” thing to do. The thing that monsters in this universe would do for one another. Though, seeing the outcome of their chat, it was pretty obvious that Sans wasn’t much good at the whole nice thing. His words would hardly have inspired hope in this universe's Papyrus. They’d instead brought him to tears, leaving the larger monster swallowed by his grief. Sans should probably go and fix his mistake.

 _I really fucked this one up._  Of course he had. That's what the skeleton did best. Sans hadn't meant to be a complete jerk. He just hadn’t realized what should’ve been obvious to him. What every other monster in his situation would’ve picked up on instantaneously. It wasn’t Sans fault that he wasn’t the brightest monster. Or maybe it was.

The feeling of guilt for his actions was unfamiliar. Being a dick in his universe typically didn’t have any lasting consequence, partly because of the fact that _everyone_ in the Underground was a prick. That was just the way things worked.

 _But I’m not in the Underground anymore._ At least, not his own. Not the one he was used to. The skeleton still found it hard to accept the fact that this wasn't his version of the Underground anymore. He was in a completely separate universe- or at least, the other monster had claimed. A different "timeline."

The Snowdin here wasn't the one he was used to. Just like the Boss of this place wasn't anything like his own, and the monsters here weren't all assholes. It was an outlandish idea, to be sure. But… just looking around the town he was in once more, Sans couldn’t believe that there might be any other explanation for it. Yet still… the thought that there might be different variations, completely opposite versions even, of every monster he had ever known, of Boss, of _him..._

It scared the living daylights out of him.

The touch of a hand on the shoulder of his jacket snapped Sans right out of his thoughts. Reacting on instinct, the skeleton pulled away from his attacker, shaking the hand off of him. As he turned to face them, Sans was already pooling together the magic he needed for an attack. Yet when his eyes met with a certain arachnid bartender, the skeleton hesitated.

 _Relax._ Sans had to remind himself that this wasn't his universe. He released the pool of magic he’d gathered. The rules were obviously a bit different in this universe.

The purple spider didn’t even seem surprised by Sans actions- if anything, she actually looked amused, letting a sly smirk form on her lips. "A bit jumpy, aren't you?" The skeleton didn't respond. _What did this monster want?_

Something about the spider put Sans on edge. Though to be fair, the same was true about every monster he had ever met. At this point in his life, it was a natural instinct for Sans, and it was one that had kept him alive for many years and counting.

The spider motioned for him to come back inside of the bar. "Why don't you come back inside dearie? I'd _love_ to have a little chat~" No, Sans decided that there was definitely something about _this_ monster that unnerved him. It wasn’t just his paranoia getting the best of him. There was something in her voice as she made the request that tipped Sans off. Like an unspoken threat, underlying the statement and ordering the skeleton to follow her back into the bar. A very unintimidating demand, that Sans doubted she had the ability to back up and force the skeleton into the bar.

Nonetheless, Sans rose to his feet and let himself be led back through the bar. On its surface, the place seemed unchanged from minutes before. Monsters were still chatting at their booths and tables as Sans and the spider walked back towards the counter. Though… there was something off about the entire atmosphere of the room. Sans caught a few quick glances from monsters around the bar, clearly aimed towards him. They were hardly like anything the skeleton would receive in his own Underground, but they certainly weren't as welcoming as the looks he had seen the first time he had entered the building.

 _I suppose I should’ve expected much._ It was hardly as if he and the other skeleton hadn’t caused a scene. Either way, Sans still sat back on his same stool from before, as Muffet reclaimed her position behind the bar. The skeleton’s curiosity had dictated that he’d have whatever discussion this purple spider wanted, and then go look for the other monster. Sans couldn’t imagine a simple conversation taking much time at all.

"Another whiskey?" Muffet asked, gesturing towards the skeleton with an empty glass.

"Uhh... yeah," Sans answered, and the spider began preparing the drink. The realization that they hadn’t paid for their other drinks came to the skeleton.

“Oh, don’t worry~” Muffet seemed to read Sans’ mind. “Pap’s a regular here. I’ll just put everything on his tab. I’m sure one day he’ll pay it off.” The bartender didn’t seem the slightest bit annoyed, like one would expect when hearing such a statement. Of course, if the spider already had sorted out payment for their drinks, then that meant their chat had to be about something else.

 _Another difference about this place,_ Sans noted, keeping an eye on Muffet as she prepared the whiskey. No harm ever came from being too careful, even if the skeleton did doubt that any monster from this Snowdin would slip something into his drink. Back at Grillby’s, no monster in his universe ever got off with not paying. All types of payment were due upfront, with absolutely no exceptions.

The bartender set down the glass of whiskey in front of Sans, poison free. The skeleton drained it once more with ease. Unlike the previous glass, Muffet had obviously made no attempt to water this one down.

 _Not much of a talk._  Sans thought to himself after the first minute of silence passed. Despite the fact that the purple spider had been the one who had wanted them to chat in the first place, Muffet paid no mind to the skeleton, instead focusing on drying glasses with a white cloth. Impatiently, Sans narrowed his eyes at the other monster. "You said you wanted to talk?"

"Yep," Muffet responded with a happy smile, yet she made no attempt to further their exchange.

"...About?" Sans was hardly used to being the one carrying the conversation. Monsters in his universe weren't much for casual chitchat. Muffet hummed thoughtfully for a moment, paying no attention to the skeleton. Sans only responded by grinding his teeth in frustration. It wasn’t until the spider finished her task and set down the spotless glass and cleaning cloth that their conversation began.

"Where you from?" The bartender finally asked, leaning forward on the counter. The question immediately took the skeleton by surprise, and the five eyes that glued themselves onto the skeleton certainly didn’t help.

"What do you mean?" Sans’ answer came a bit too quickly. The other version of Boss had told her that Sans was his brother, which was technically the truth- or a version of it. So why was she now asking where he was from?

"Well, I think it's pretty obvious that you're not  _really_ Sans~" The spider said playfully. "I mean, you're nothing like him."

"I..." Was it that stark of a contrast? "I'm not?" Sans had assumed that the two of them looked sorta alike. The other skeleton had even said there were at least a few similarities between them.

"What, you think I wouldn't notice? It's so obvious~" The spider giggled. "And it’s not just your clothing. Papyrus treats you like a completely different monster," Muffet smiled easily, picking up Sans' empty glass and moving it into a sink on the service area of the bar. "Not to mention the fact thatPap would never let his brother drink alcohol. He's more protective of him than any other monster I've seen. But then here you come, strolling in, claiming to be Sans. So, I guess you can’t blame me for being the littlest bit curious. Just who are you?”

 _Sans._ The skeleton knew telling her that was actually his name would be pointless. It was apparent Muffet wouldn't believe him, and if he tried explaining the timelines and universes debacle to her, the skeleton would probably come off as a raving lunatic. He himself was still trying to wrap his head around the seemingly ludicrous idea, and he had witnessed it firsthand- imagine trying to explain it to someone who’d only ever known one version of their reality.

"It's just that, Pap's been coming here for ages.” The spider seemed totally lost in thought as she casually sat her head on one of her left hands. “We've gotten pretty close over the years. And we’ve talked about _a lot_ of things.” That same knowing smile wiggled onto her lips. “But, you know… never once has he mentioned to me another skeleton who looked almost  _exactly_ like his little brother," The spider’s expression quickly flipped into a frown. "Just seemed like the kind of thing that would've come up in conversation. With how much he talks about his little bro, it actually seems _impossible_ that something look that would never come up."

"My name is Sans," Five eyes rolled sarcastically in response to the skeleton’s claim. Predictably, the spider didn’t buy it.

"Alright,  _Sans._ Why don’t you go on and tell me where you’re from? Waterfall? Hotland? The Capital?" The spider’s gaze narrowed in on the skeleton. “The Ruins?” Sans had no clue how to answer. She probably wouldn't believe him if he said Snowdin, and she definitely wouldn’t believe him if he said another universe.

The spider shook her head in disappointment once it became clear the skeleton didn’t have an answer for her. "Ah, I see. Well, it really doesn't matter, anyway." The elbows of the spider's top two arms pressed onto the top of the bar as she leaned forward, closer to Sans. A bit too close for the skeleton’s comfort, but Sans resisted the urge to back away.

"What does matter is the fact that I've never seen Papy so upset before just now. I mean, I've seen him through some rough patches, but nothing close to that," In the spider's eyes, there was some sort of distant look, as if she was recalling a memory of long ago. Besides that, her expression was almost completely blank. The playful attitude she had held only moments before was gone.

"And I’ve never seen Papyrus cry like that. Oh sure, I’ve seen him cry before, but never once has he ran out of here sobbing.” The spider’s eyes were locked with Sans’ own, and the skeleton felt like he had a good idea of where this was heading. “Pap’s a pretty tough monster. He might not look it, but it takes _a lot_ for something to get underneath his skin." The spider leaned in closer still. The two of them were less than a foot apart now, and when the other monster’s mouth opened once more, Sans could feel a chill run down his spine as Muffet’s soft whispers, hissing with rage, were made directly to him.

"Now, I don't care about whatever it was you said or whatever you did to make him like that. What I do care about is making sure it never happens again. If I have reason to even _suspect_ you’re purposefully trying to hurt him, then _I will make your life a living hell._ Every monster in all of Snowdin will help me do it, too. By the time we’re done, you will be hurting, much, much worse than that. You’ll be wishing you could still run away sobbing.”

Muffet slowly pulled away from the skeleton, a fake but convincing smile, obviously perfected with some practice, fell over her face. “Are we clear?”

The way the spider played it off with ease almost made the skeleton question if he had heard her correct. Everything else in the bar; the other monsters, the noise, the differences between it and Grillby’s that stuck out to the skeleton like sore thumbs, all of it, seemed to fade into the back of Sans’ mind, like muffled radio static. The purple spider had threatened him. And it had most certainly been made as a threat.

 _A threat._ It took Sans a moment to process it in his shocked state. The skeleton was used to threats. He’d probably exchanged more threats in one day than all the monsters in this universe did collectively during their lives. The thing that got him was that he hadn’t been expecting the purple spider bartender of this universe to make one. And with such smug certainty, too.

The skeleton could see the arrogance showing in the smile on the other monster’s face as she misinterpreted Sans’ surprise as a sign that her threat had made its point. “Oh dearie, there’s no need for fright~” The playfulness was back in droves, like it had never disappeared in the first place. “Just be sure that it never happens again~”

“Is that really the best you’ve got?” The cheeky grin fell from Muffet’s face like a ton of bricks once Sans recovered from his disbelief. “I mean, come on. I get that you all aren’t exactly used to that kind of stuff, _but seriously?”_

“Ex- excuse me?” The spider’s misplaced confidence quickly faltered after seeing how little her threat had affected the skeleton.

“Have you ever been in a situation even _slightly_ resembling some form of danger?” Red eyes pressed against Muffet’s, burning violently in rage. If this purple pansy thought she made the skeleton even the slightest bit afraid, then she was sorely mistaken. What made this pathetic weakling think she could threaten _him?_ After everything Sans had been through. After every restless day he’d lived, and all the equally sleepless nights. Through the endless betrayal he suffered, and all of the brutal, unending _violence_. The skeleton had seen shit that would make the monsters of this place curl up into a ball, whimpering. And yet she still had the nerve to challenge him. “You don’t even have a clue, do you?”

“I- uh…” The purple spider tried to find the words for an answer, but the skeleton’s response had thrown her so much that she was able to do so. Sans’ eyes scanned he in an instant, taking in all there was he needed to know.

_* LV 1 - MUFFET – 8 ATK 0 DEF  
* Bakes pastries full of love. And sometimes squishy, eight-legged raisins._

A quick check confirmed what the skeleton already expected: a monster whose life had been filled with sweet ignorance of what monsters were _really_ capable of. “You think _you_ scare me?” Sans pressed, glaring into the unintimidating gaze of the spider’s five eyes. “You?”

The skeleton chuckled, but he could sense the anger boiling inside of him. His irrational fury was pointless to waste on this little purple spider who didn’t really deserve half of his rage, but it was impossible to hold back. Sans felt like a dam had burst inside of him, and years of pent-up anger were spilling out of him, raging waste to the nearest target, who just so happened to be this monster who had been foolish enough to threaten him.

Sans stood, still returning the other monster’s threat. “Why should I be scared of someone like you? You’re just some monster who’s lived a cozy, happy life. A life devoid of any real pain or even the slightest bit of struggle,” Sans realized he was raising his voice now, and the other monsters of the bar were probably all staring silently at his outburst, but he couldn’t bring himself to care. _Good._ Let them stare. Let them understand just why they shouldn’t even _think_ about messing with him. His speech was just as much addressed to them as the arachnid bartender. “You’ve never had to fight for the right to exist, every day of your goddamn life. For the ability to live and breathe for another day of your miserable existence.”

“You’ve never faced any hardship, and you expect me to be scared of you? You expect me to even take a threat from you seriously? Surely, you must be joking,” Sans had seen the drunks at Grillby’s make more intimidating statements. “I wonder, do you even know what it’s like when a monster dies?” The image of it was forever burned in Sans’ mind, after witnessing a seemingly infinite number of monsters dusted, but the skeleton wondered if this puny spider had ever seen it at all.

 “They turn to dust,” The spider replied quietly, as if she was afraid of the other skeleton- _which she should be._

“Oh, there’s _much_ more to it than that,” Sans would be lying if he said he wasn’t enjoying the look on the spider’s face as she flinched in fear- fear of him. “First, the disintegration begins around the fatal blow. From there, it spreads outward, to the surrounding area. It doesn’t matter what kind of monster you are; skeleton, mammal, reptile, fish, _spider,”_ Sans made sure to stress that last one. “Each part of the monster turns to nothing more than dust, until there’s just one part of you left- your soul.”

“But that- that doesn’t turn to dust. Oh no,” All Sans needed to do was close his eyes, and he could vividly picture it in his head. “It **shatters** ,” The skeleton’s fist slammed to the counter. “Into a million little, unrepairable pieces that then dissolve into nothingness.” Sans laughed maniacally, the images engraved in his mind after years of seeing the process repeat itself, over, and over, and over. Even a universe away, he still couldn’t escape them. “And then nothing is left but a pile of dusty ashes and the last outfit that forgotten monster will ever wear.”

The skeleton leaned onto the counter, mimicking the spider’s same movements from moments before. “So you make your cute little threats. You tell yourself you can take someone like me. You tell yourself that this entire fucking town can take me. It doesn’t matter. If you- if anyone-” Red eyes glared accusatorily across the bar, and all the other patrons made a point not to meet his gaze. “Ever comes after me, then they’re as good as dead. I will obliterate anyone who even _thinks_ of attacking me or my br-”

Sans stuttered for a second, choking over his own words as he realized what he had been about to say. _My brother._ Before Boss had become part of the Royal Guard, Sans had been so used to making threats to keep the both of them safe. In his rage, he failed to separate the two of them in his mind. Quickly Sans recovered, returning to his silent glare over the crowd.

“Are we clear?” The skeleton tried to keep a stone-cold expression on his face as he turned back to the purple spider who was anxiously staring back at him. The other’s fear, which he had taken joy in only a bit before, suddenly left a wrenchingly bitter taste is his mouth.

The second monster bit her lip and nodded her head solemnly, but the skeleton didn’t notice nor care. Sans had already turned and began walking out of the bar, wanting nothing more but to leave the place behind him as a distant memory.

* * *

The town of Snowdin seemed to fade away as Sans walked through it. Burning red eyes focused on the only thing that felt familiar, the only thing that the skeleton was sure was real- the snow beneath his feet, and the constant crunch of each step he took. Sans didn't really know where he was going. To be honest, he didn’t care. The skeleton just let his feet take him to wherever it was they were going. Anywhere was better than back there, in Muffet’s.

 _That was a mistake._ One of many he had made in the short few hours he had been in this alternate reality. _I got carried away._ _I went too far. I was an asshole._ Again. Seems like that was a pretty common theme for Sans.

Though, all of that had been obvious. Even during his long tirade, a part of him had known just how unreasonable he was being. But that hadn’t mattered, because it had just felt _so good_. Pouring his anger out had only been part of it. Feeling so… in control. So powerful and _feared._ The sensation had been undeniably euphoric. Or at least, it had been, for a very short moment before the skeleton recognized the terrifying familiarity of the whole situation. Sans had seen firsthand what power did to monsters- to one in particular. He never wanted the same thing to happen to him, but for a moment, he had let it.

And that absolutely disgusted the skeleton.

Sans’ strides began to move faster, as if it was possible for the monster to simply walk away from the sour feeling that his outburst had left him with. It wasn’t, but that logic didn’t keep the his feet from trying.

The most surreal part of the whole experience had been their reactions- the responses of all those monsters in the bar, written blatantly on their expressions; the fear on their faces as they purposely shifted their sights away from the skeleton under his gaze, and how they seemingly shrunk as Sans’ red eyes bored into them. Those reactions had been completely unexpected. The skeleton had never seen a monster look so terrified by simple threats Sans had made. Or threats that any monster made. In his Snowdin, those attempts to intimidate other monsters were made so often that they could hardly make even the jumpiest monster visibly squirm. Monsters had become so accustomed to the practice that they’d become numb to it.

 _But it was different here._ Because everything was different here. Because Sans was in an alternative reality of his own. Because he had swapped places with this other universe’ version of himself. Because who knows why.

 _This is all crazy._ The idea that such a crazy idea was starting to sound normal to him was in itself crazy. _This may be real- no,_ this was real, and Sans knew that. _But that doesn’t mean this isn’t still crazy, too._ This wasn't just some fever dream or some hallucination. The skeleton really had switched to some distant universe. A universe that had all of the things Sans’ was lacking, and lacked the things it held in abundance. He’d appeared in an Underground full of monsters who were nothing like the murderers and perverts Sans was used to. A universe full of monsters who got along and looked out for one another.

 _Which was crazy._ Like all this was.

Monsters in this timeline cared about more than just their own skin. They were there for each other, despite the fact that they had nothing to gain from it. Even Muffet’s threat was motivated by selfless intentions. The bartender had tried to intimidate Sans into not hurting the Boss of this universe again, simply because she cared about him.

That, too, was ridiculous. Caring for another monster besides yourself only put you in a position to be hurt, to be used. Sans knew that all too well. Yet the monsters of this universe seemed to have a completely different attitude towards what would typically be seen as weaknesses and flaws in Sans’. They treated the idea of caring for others like it was normal.

The Boss of this reality cared about his Sans. He had wept at just the thought of the danger his brother was in. And the purple spider cared about Papyrus. Because they were “friends,” Muffet would put herself at risk just to keep the larger safe. It was a ludicrous idea: monsters putting themselves in danger to keep another safe- or, more accurately, to keep them happy _. Just more crazy._

 _Happy._ That wasn't exactly an emotion Sans was all too familiar with. The main concern in his life had always been survival. It was that way for all the monsters in his timeline. Happiness wasn’t exactly a priority when you could be dusted at any moment if you’re not careful. Perhaps that was why the skeleton lived with the constant abuse. Maybe that logic had been the reason his life had turned out so fucked up in the first place.

In his universe, Sans had never been happy. But he had been safe. Or at least, as safe as he could possibly be in a place like the Underground. And he’d always thought that was good enough. Survival was a lot to ask for in a land of relentless killing. Happiness would’ve been nothing more than a wistful thought- some half thought up dream, that no monster could ever hope to achieve.

But not here. Here, safety didn’t seem to even be a concern. Monsters roamed freely through the Snowdin town square, not afraid to step outside their homes. The monsters of this universe weren’t busy raging wars on every other monster. Here, the inhabitants of the Underground lived peacefully, together. Happily.

_Crazy. All of it was just that: crazy._

Sans could feel the teardrops accumulating around his eyes once more, soaking his red pupils. This time, he didn’t bother trying to hold them back. The skeleton wasn’t sure he could, even if he wanted to. The skeleton let the tears drift silently to the ground, trailing down the cheekbones of his skull.

 _It wasn’t fair._ None of this was. His entire life had been nothing but unfairness. And he’d been able to live with it, because that was just how life _was,_ for everyone. There was no justice in the world. The universe was cold and uncaring, and the everyone in it just had to get used to the idea.

 _But this… this is just too much to handle._ Even for Sans, who thought he’d steeled himself for everything. It was as if the universe had made its personal goal to make Sans miserable. For years, he’d spent his life being kicked to the curb, putting up with all the bullshit and abuse and the hurt and the injustice, and now the universe had rolled his beaten body over, picked his skull out of the dirt, and laughed in his face by showing him _this._ This picture-perfect version of the same Underground Sans’ had spent his wasted existence in. This impossible possibility. This untouchable fairytale. The one thing Sans wanted out of life that he didn’t even have the chance of getting.

If it was up to him, the skeleton would never leave this place. He’d never go back to his timeline. Nothing awaited him there. Nothing pleasant, at least. When he’d been young, he’d spent his entire life protecting his little brother. But now, Boss was the leader of the King’s personal combat unit. Of all the monsters in the Underground, he needed protecting the least. Sans’ very presence harmed his brother’s image. His very existence ruined him. Disappearing forever was probably to best thing Sans could ever do to protect Boss.

But Sans couldn’t stay here. He couldn’t live in this version of the Underground that was better than his own in every single way. The skeleton couldn’t hope to ever be happy here, in this place of his dreams, because there was no way he could ever stay here.

His appearance had been entirely unplanned. Entirely random. He didn’t have any control of it. Who’s to say he wouldn’t end up back in his reality, in a few hours or minutes? Hell, who’s to say he hadn’t returned to his timeline while he had been walking, and he just had been so deep in thought that he hadn’t noticed?

The skeleton glanced up, not knowing what to expect. His sights fell on a small brown guard post, that he found familiar even in this universe. His post. Guess it was kinda hard to break old habits, after countless years of sticking to them religiously. Sans’ feet had carried him to the place he spent his days, his worthless guard post in the abandoned corner of Snowdin forest.

The skeleton kept walking, knowing there was no need for him to watch his post here, in this universe where the monsters seemed _incapable_ of committing a crime. Further along the path was a bridge with bars so widely spaced that Sans had no trouble moving his way through. His feet kept wandering until they had no choice but to stop, at a large purple door. _The Ruins._ Sighing, Sans slid down against the wall beside the door.

“I can’t stay,” The skeleton could feel what little unwanted, undeserved hope he had left disperse as the words sounded aloud, as if saying them to himself made them anymore truer than thinking them. The only answer Sans received was silence- something he should’ve expected being in the middle of nowhere. No monsters ever came this close to the Ruins. There was no reason to. Without being able to get past the door, there was no reason to come close to this place.

He liked places like that… sometimes, at least. Places where he could be completely alone with his thoughts were a double-edged sword. It gave him some peace and quiet to sort out whatever was on his mind, but it also meant nothing could distract him from his own thinking.

There was one spot he had, just outside of Snowdin, where he could be completely by himself. It was a small pond that no other monster ever visited. The skeleton kept it a complete secret to himself. No one besides Sans even knew about it. Not the Guard. Not any of Snowdin’s residents. And especially not Boss. He’d have a shit fit if he ever discovered Sans sneaking off without his permission.

Would that same clearing exist in this universe? _Probably,_ Sans decided. He had yet to see anything completely new in either of the universes. Everything was just twists on what the skeleton was familiar with.

 _Which was probably why the other skeleton had referred to them as parallel universes in the first place._ Everything was changed just enough that collectively, it made a drastic difference. The temperature, the attitudes of monsters, how they handled different situations; it was like all of it had been slightly tempered with. The monsters of this world had been molded into softer and less aggressive people, who were much less prone to the violence Sans was accustomed to seeing.

 _Which was why I can’t stay here in the first place,_ Sans thought sourly, his finger idly trailing through the soft, undisturbed snow. Not only did he not fit into this place, but universes away, there was a skeleton who looked somewhat like him _definitely_ not fitting into Sans’ world. Another skeleton was busy living in the personal hell Sans had suffered through for years. A skeleton who would have no idea how to handle the violence, or abuse, or the thousand other complications of Sans’ life.

To be truthful, Sans couldn’t give less of a shit about the other version of himself. Why should he? He’d never even met his double before, so for what reason should he care? What could possibly make him give two shits about what happened to his doppelganger, being beaten in Sans’ place?

But that wasn’t the point, and the skeleton knew that. It didn’t matter whatever selfish decision Sans made. It didn’t matter that he was just looking out for himself, like every monster should. He’d end up back in his universe, one way or another. Either he’d suddenly find himself back home, in his hellhole, or some other equally crazy event would take place. Because he certainly didn’t deserve a life like this, and all the universes that had ever existed must’ve known that.

 _It’s better to just accept that fact and move on._ The longer he entertained the thought of living a happy life, the worse off he’d leave himself. The more he let himself imagine the possibilities of happiness and a good life, the bitterer he’d be when he returned to his reality. This seemingly perfect dream would be ripped from his hands eventually, but preparing himself for it now would make it hurt less, much less, than if he let himself be happy for the undoubtedly short time he’d be here.

The skeleton closed his eyes, taking a deep breath. He let his mind drift away from him as he tried to regain his composure. Rather than pay mind to the thousands of questions and uncertainties just being here brought up, Sans instead decided to concentrate on the immediate feelings of his surroundings; the slightly cold chill against his bare face and ungloved hands, the heat insulated inside of him, between his two thick layers of clothing, and the purple rock wall behind him, pressing hard against his spine. Before he knew it, the silent tears had stopped, and his red eyes were opened, the skeleton feeling in control of his emotions once more.

 _…Alright._ Time to focus. He’d gotten so distracted by his thoughts that he’d forgotten entirely about the other version of Boss. Quickly, Sans wiped away the lines of tears that stained his cheeks with the cuff of his jacket. _I should go and find him._

Finally getting his act together was only half of the problem, however, because Sans still had to find out just _where_ the skeleton would go. The way he had disappeared instantaneously outside of Muffet’s without a trace made Sans wonder if the other skeleton shared Sans ability of shortcuts. For as useless as the skeleton was, that was one thing unique to him. Sans didn’t understand it, or how he did it, or how he’d learned to do it, but that didn’t matter. The only important thing about being able to teleport anywhere in the Underground in an instant was just how useful it was. Yet, if the other monster had access to the same skill… then finding him could prove much more difficult than Sans would’ve hoped.

The house he had woken up in seemed like the most obvious answer. Whenever Boss was in a bad mood, he usually locked himself in the version of the house in Sans’ universe. Or beat Sans. Or both. Really just depended on the mood, and whatever Sans had done recently to piss him off.

 _So I need to get back to the house,_ Sans decided, closing his eyes. When his red eyes opened back up, the skeleton found himself sitting against the wall of a very familiar home- or, more specifically, this universe’s version of it.

Sans soon discovered another change between their two timelines: locks. In this version of the Underground, monsters thought it was a smart idea to just leave doors unlocked. Which just felt stupid, however peaceful this place may’ve been. Though, Sans probably had no right to complain, because that one little difference between their two universes made the job of getting back into the house much easier on him than another shortcut.

The sound of the slamming door, echoing through the hollow interior of the house, was the only noise that filled the room besides Sans’ quiet footsteps as he entered the house’s living room. The skeleton had an immediate suspicion that the place was empty.

"Pap- Papyrus?" It felt so very strange to call his brother's name out. Not only because Sans was looking for a monster who wasn’t his brother, but because he never referred to his brother as anything other than Boss anymore. Still, no skeleton answered Sans' calling. Which meant the larger monster was either not here, or purposefully ignoring him- a very likely possibility after how much Sans had upset him.

A quick scan of the first floor revealed what was pretty much evident to anyone who walked into the house: no orange hoodie wearing skeleton. The kitchen and the living room were both empty, and the same was the case with the small bathroom by the bottom of the stairs.

With no space left for the other skeleton to be on the first floor, Sans quickly ascended the same stairs he had descended from probably just two hours ago. Two hours that had felt like an eternity, with how much Sans’ life had been turned around. As he reached the top of the stairs, Sans found himself directly before the other Papyrus’ room, sealed by a closed door that the skeleton was certain he hadn’t shut that morning.

As the wooden door creaked open, what part of Sans had already expected was confirmed. There was no sign of the other skeleton. The larger monster may have come back to his room, but he had left before Sans could find him. _Obviously it wouldn’t be that easy,_ the skeleton told himself as his bony hand released its hold on the doorknob, letting it snap back into place. It seemed like the only other thing that had been touched since Sans had last seen the room was the cardboard box full of paper and parts, moved from its corner to the larger skeleton’s bed- hardly much of a clue as to where he might now be. Other than that, it seemed as if the place was completely undisturbed.

Sans sighed in disappointment as he pulled away from the open doorway. A glance down the hall brought the last room into Sans’ sights: his room- or rather, his double’s. _I wonder what this universe’s version of my room looks like._ Sans couldn’t help but be curious of what the bedroom looked like as he strolled slowly down the hall, knowing that the remaining room was the last place in the house the other skeleton could be.

Sans’ own room was small and messy, with a twin sized mattress lying on the ground as his bed and a cheap, cardboard box serving as a nightstand- just like in this universe’s version of Boss’ room. Yellow bottles of mustard and empty glass containers once filled with alcohol littered the floor, complimented by the skeleton few strewn about articles of clothes- neither him nor Boss were ones for cleaning.

This Sans must’ve undoubtedly had a room very unlike his own. _As for what would be so different about it…_ _uh…_ Sans struggled to take a guess. _There’s probably a lot of… blue._ That’s what the other Papyrus had said his brother’s favorite color was, right? Blue. There was a good chance this Sans’ room might’ve been that color. But beyond that, the skeleton was lost to any other prediction he could make.

 _Welp._ The skeleton swung the door to the room open, revealing it’s interior. He had been right about the blue, that was for sure. He had been prepared to see a lot of the color, yet it still somehow managed to overwhelm him. Almost everything was blue; the walls, the ceiling, carpet, bookshelf, and even the closet door. The only nonblue furniture in the room was a brown table and desk, which both stood like islands in the one-color ocean.

 _No Papyrus._ The thought raced through Sans mind the second his eyes completed their first pass over of the room. Disappointment flooded the skeleton for but a brief moment, quickly being pushed to the side by the urge to explore his other self’s room. It was like he was almost in a trace, letting the sea in blue engulf both him and his attention and he took it all in.

It wasn't messy, so it was completely unlike Sans’ own room in that regard. In fact, it was unnaturally clean. Every aspect of the room was perfectly tidy and ordered. No clothes littered the floor, nor even a piece of trash. The light blue carpet should’ve been an easy giveaway to any stains, but the skeleton couldn’t find even a spot. The room was immaculate, even despite the fact that it wasn’t exactly a small space to keep clean, either. This Sans’ room was easily the bigger of the two bedrooms in this version of the house. If anything, it looked about the same size as Boss’ room.

Turning his attention back to the furniture that filled the room, the first thing that grabbed the skeleton’s attention was the towering aqua blue bookshelf beside the closet door. It was crammed full of books- a majority of which appeared to be large picture books. On the other side of the door was the outcast brown desk from earlier, sitting in the corner of the room beneath a window whose blinds hung open, allowing light to pour into the room. Hanging on the wall in another corner of the wall, right next to the low table, was a large poster that Sans’ eyes quickly glanced over, not recognizing the picture of planets and stars he had never seen before.

The last part of the room was the bed. Saying it had surprised him was an understatement- Sans couldn’t have ever imagined anything like it. The skeleton didn’t even know where to begin describing it. The bed was blue, of course, _because why wouldn’t it be_ , yet that hardly did it justice. The idea of sleeping on a bed like this, even for one night, was mortifying to the short skeleton. Sans thought he would prefer to sleep on his dirty, frameless mattress, or even in the cum-soaked sheets of Boss’ bed than something as humiliating as this. It could hardly be called an upgrade from Sans’ bed. Its very existence was a crime against monster-kind, yet here it was, sitting in his double’s room, looking like it had been there since the dawn of time.

 _A racecar bed._ No way around it. This parallel universe’s version of his room contained what may have been the most immature things Sans had ever seen. And it had clearly seen much use, judging from how the mattress sagged into the questionably styled bedframe even with nobody on it, broken in over years of the same monster sleeping on it. _How childish._ The thought slipped into Sans’ mind, and the skeleton couldn’t deny the truth behind the statement. There was a racecar bed, sitting in this universe’s version of his room. _How can **any** version of myself willingly sleep on such a juvenile thing?_

Sans knew the answer even as he asked the question. In fact, he had known the answer the moment he’d stepped into this Sans’ room, and seen the stacks of picture books sitting on the bookshelf.

 _God, he’s just a kid._ The rows of Sans’ sharp teeth gritted hard against each other, bone grinding anxiously on bone. Picture books, a racecar bed… Sans hadn’t even noticed the toy figurines lining the brown table next to the bed until now. It was so childish and immature, exactly what he’d expect from a kid in this version of the Underground. This universe’s Sans was nothing but a child himself. _An innocent little kid._ A naïve fool, now stuck in place that had little care for innocence.

Sans wasn't one to sugarcoat things. He’d learned from experience that the truth was more often than not unrelentingly brutal, and cold-heartedly unempathetic. Yet being honest with himself was necessary. The skeleton could try kidding himself about things all he wanted, but Sans would always be stuck in the same place- already knowing deep down what he was too afraid to admit to himself. Though even for him, it was hard to admit the truth now. But it was clear to the skeleton what the cold truth lurking beneath the surface of this situation was.

Sans’ double would need more than just luck if he hoped to survive even twenty-four hours in his place. And the skeleton would need _several_ miracles to stay alive until this whole situation sorted itself out, with them swapping back places. Hell, in all truthfulness, the skeleton couldn’t imagine the other not already being dead. All it would take was one misspoken word to Boss, or anything that might attract the attention of any of the other assholes in the Royal Guard. Sans had learned to handle situations like that, over years and years of the reoccurring nightmare scenarios, seemingly playing on loop, and he still only _barely_ managed to come out the other end of it all alive. _What chance did a monster like this have?_

 _Poor guy._ A twinge of that same feeling from earlier- guilt- pulled at Sans’ soul. Even though the skeleton had been dragged into this whole series of events just as much as the other, he’d certainly received the better half of the unknown deal. He’d been jolted and confused when he’d woken up in this happy go lucky reality from the hellhole that was his timeline. Sans couldn’t imagine the feeling that must come with it all happening the other way around.

The skeleton sighed, hanging his head in shame. He didn’t want to be in the skeleton’s bedroom anymore. The version of Boss he was searching for wasn’t even in here, either, so it was pointless for Sans to hang around any longer, unless he wanted to make himself feel even worse about his double’s chances of survival.

 _Where else could this Papyrus be?_ The skeleton asked, forcing himself to focus on something else- on something he could fix- as he shut the door behind him and resisted the urge to look back into the room of the poor skeleton who was almost certainly going to die in his place. He’d already checked all of the rooms in the house. _Maybe the shed outside?_ It didn’t make a lot of sense, but it was all the skeleton had to go on. Plus, it felt a hell of a lot better to be doing something than letting his mind wander back to the morbid realization still hanging over him.

 _Wait._ The skeleton paused as the not so chilly outside air hit him and the door behind him slammed shut. He hadn’t checked all of the house, he realized, because there was still a room left, hidden in the back. The skeleton almost never went in there, and Boss rarely did the same. It was just an empty room without any purpose or use. Even though it seemed unlikely, maybe that was different in this universe? If there was a possibility that this timeline’s Papyrus might be in there, Sans had to check.

The skeleton walked along the perimeter of the house to the back of it, where another door sat, exactly like in Boss' house. Surprisingly, the door was locked, which Sans quickly discovered when he tried to tug at the doorknob. Monsters in this universe did decide to lock some of their doors, annoyingly enough. Before he could attempt to teleport into the room, the skeleton’s eye was caught on a small silver object, glittering obviously beneath the few bits of snow that had been thrown on it in a half-assed attempt to hide it. Seconds later, bony fingers grasped a cold, metal key.

 _An “A” for effort, at least._ Sans thought to himself, sliding the key into the lock. Hiding it directly beside the door it was supposed to keep locked only _slightly_ defeated the purpose of locking it in the first place, but at least they were trying. An audible click rang out as the key turned in the knob, and Sans was able to push the door open.

 _Woah._ Red eyes fell onto the tiled floors and light blue walls, and opened wide in shock. It looked nothing like the back room in Boss’ house. And as he stepped inside, he learned it wasn’t exactly empty, either.

 _What is this place?_   Sans scanned the room. A big, bulky… something sat beneath a blanket in the corner of the room. Blueprints littered a counter on the other side of the room, along with papers seemingly thrown carelessly about. _Research._ The other monster’s reply from before suddenly made much more sense. Which made this place what- a lab?

A lab. That felt about right to the skeleton. He couldn’t think of any other way to describe it. But that conclusion only brought on another onslaught on questions. Like, “why is this here?” and “what exactly is he researching?” This was the first thing in this universe that was a completely unlike Sans’ own. This room wasn’t just a slight shift in appearance or attitude from what the skeleton was familiar with. It was something completely new and separate from the pattern. Why?

 _No Papyrus._ Despite the interesting discovery, Sans couldn't help but be discouraged. If the skeleton wasn’t here, he almost certainly wasn’t in the shed. The last place Sans had thought to look was yet another dead end. Or at least it seemed. Red eyes looked about once more. Maybe this place held some clues about the other’s whereabouts? It was a weak lead, but better than nothing at all.

 _Right. Umm…_ Obviously, the skeleton was immediately drawn to the large covered item in the corner of the room. He pulled on the purple sheet on top of it, letting it fall to the floor as it revealed what lie underneath. Then, Sans could do nothing but stare at the unrecognizable metal mass, mesmerized by it.

 _It’s some short of machine._ That was all he could get out of it, after almost a minute of him attempting to understand what he was looking it. The machine was misshapen and deformed, clearly not in any sort of working condition. It looked like it’d been through hell. Somehow, the metal of the machine looked like it had been melted. And not as in the wielding pieces of metal together sort of way, either. It was like parts of the machine had _literally_ been melted by something hot enough burn through iron alloy.

Yet that wasn’t it, either. Someone had intentionally begun to tear the machine apart, ripping out the outer panels and revealing the inner workings of it. The wires of the interior of the machine hadn’t been spared from heat-related damages. The plastic outer layer of the cables, designed for safety, had been melted off at the ends of wires, which seemed to cut and fray randomly, no line completely intact.

 _I don’t know what any of this is,_ Sans admitted, backing away from the machine. He didn’t want to mess with something that could easily shock him to death. Even if the mechanism seemed to hardly be in working condition, the skeleton wasn’t about to risk his nonexistent skin to find out. The machine wasn’t even any help for him in the first place. Sans doubted that hidden in the wreckage of it was some sort of clue to the other monster’s location.

 _What else?_ The skeleton looked at the piles of blueprints on the counter a few feet beside him. They too proved little use to Sans’ efforts. Most contained various rough hand sketches of machines similar to the broken one he’d just seen, and were covered with illegible chicken scratch that was reminiscent more of pictures than understandable words.

 _Useless as well,_ Sans told himself, scouting the counter for something at least readable. His view stopped on the piles of white papers. At least they appeared to be written in a language Sans could read. Hurriedly, he grabbed one and quickly skimmed over its contents.

“Ugh,” The skeleton dropped the paper carelessly to the ground. It was some sort of journal entry from who knew how long ago. How exactly was that supposed to be useful to him? Sans didn’t want to know how the other monster’s day had been however many weeks ago. He needed to know where the other monster was, _now._

 _What’s the point of all this?_ Sans couldn’t help but get frustrated, just looking at the surplus of papers. It would take him forever to read through them all, and even that didn’t guarantee he’d find an answer to where the other skeleton was.

 _Is all this research on the timelines?_ The larger skeleton had said that was how he’d known about the topic. _But why did he even bother to look into something like that at all?_ This Papyrus couldn’t possibly have known some switch like this would happen. _So why had he done do much research on it in the first place?_ Unless he wasn’t researching that at all…

It was all so much that Sans’ head was ready to spin, and that was saying something, since he was started to get used to having his head filled with more questions than answers.

 _Alright, Sans, focus._ He told himself, tearing his eyes from the lab work. _Is there any sort of connection this all might have with something else?_ Anything at all? Some sort of place in the Underground that might have any relation to this secret workshop?

 _The Lab._ The realization shot into Sans’ mind faster than a racecar bed. Not this one, of course, but the lab in Hotland. Where the Royal Scientist worked- or at least, that’s how it was in his universe. If this version of Boss was into science stuff, there was at least chance he was there. It might’ve been a bit of a leap in logic, but if there was even the slightest possibility, Sans needed to check.

Rarely did the skeleton ever go to Hotland. Boss and him had passed through it a few times on their way to the Capital, yet that was about it. There was nothing for anyone to see on the boiling hot cliffsides.

 _Guess that changes today,_ Sans decided, preparing a shortcut to the lava contaminated area. In a blink he was there, the trick only eating away at some of his remaining magic reserves. When his eyes opened once more, they were greeted with the bright reds and oranges of magma and dirt, rather than the moody purples and blues of the lab, confirming what he could already tell from the heat- he was in Hotland.

Speaking of the heat- if Sans had thought his two layers of heavy clothing had been a bit much for Snowdin, the same was ten times as true here. Under his usual apparel of a hoodie and sweater, it felt as if the marrow in his bones was boiling.

 _This lab better have air conditioning,_ The skeleton offhandedly complained to himself, his feet already moving towards the main intersection of Hotland. If he had been a dick before, he was gonna act like a _real_ ass in the scorching temperature.

 _There._ He could spot the giant red sign spelling out “LAB” a mile away. Thankfully, it meant Sans didn’t have to do much guessing to figure out the giant white building straight across the intersection from him was the one he was looking for.

Back in his reality, the Royal Scientist was known for her needlessly cruel experiments. She was feared about as much as the Royal Guard. Hell, maybe even a little more. The Guard could kill you, that was true, but she could turn you into an unrecognizable abomination, torturing you with who knows what, and _then_ kill you. Her test subjects never saw the light of day after going into the Lab.

The same probably didn’t hold true in this timeline, but that still didn’t exactly comfort Sans much. Part of the skeleton was urging him to turn and run, wanting absolutely nothing to do with this lab. It was screaming and kicking and fighting against Sans’ each step, holding nothing but distaste and unfounded hate for a place he’d never even been to.

 _I’m probably just nervous about the Royal Scientist._ Sans told himself, pushing the feeling down. _I’m sure she’s nothing like how she is in my universe._ His reasoning didn’t calm the feeling filling his soul.

There were voices coming from the lab. Angry voices, that the skeleton could only make out as he got closer. It sounded like two monsters were arguing. One voice belonged to a newcomer, who was busy stuttering out responses to the other’s demands. The other was a voice that froze Sans in his tracks. A voice that sounded just like Boss, whenever he got too drunk or really angry- whenever Boss’ rage was the only thing controlling his actions. _Don't be stupid._ Sans knew Boss wasn't here. His brother couldn’t be here. _But… I’m here._ So why couldn’t Boss be?

 _Shut up._ The skeleton knew he was being absurd. It was just this universe’s version of Boss, their voices sounding almost identical when they were angry. And the other skeleton did sound _angry._ The closer Sans got, the clearer the voices became. It was evident that the pair wasn’t having a nice, if not a bit loud, chat.

"-impossible! You know better than anyone else it can't be done," The owner of the second voice said, in a high-pitched squeal. Probably some female monster, judging from that alone. Possibly the Royal Scientist, but that didn’t feel right to the skeleton. The speaker’s voice seemed weirdly familiar.

"I can't just abandon my brother with some murderer!" The voice of Boss screamed back, full of the same desperation the larger skeleton had earlier. Sans was only a few steps from the door at this point, his pace slowing to a crawl. They were obviously talking about doing  _something_ to help the other Sans.

"No… you’re right,” the second monster answered, their argument beginning to die down.

"Please," Papyrus began. He had stopped screaming too, and his voice sounded much more like that of the skeleton Sans had talked with in Muffet’s. The second skeleton lowered his voice to no more than a whisper, and Sans couldn't quite make out what was said. The other monster murmured something back, also too quiet for Sans to hear.

 _What are they saying?_ Sans thought, unable to contain his curiosity. Slowly, he pressed the side of his skull against the door, hoping to eavesdrop. Yet the moment his bone touched the metal of the entryway, the doors parted automatically.

Sans jumped back surprised, and the two heads of both monsters turned and looked at him, four eyes falling on him as he silently cursed this universe’s advances in motion technology.

“So you _are_ here,” Sans’ red eyes didn’t even glance at the stranger as they spoke, wide-eyed in amazement. His eyes instead traveled to the taller skeleton staring back at him. The other version of Boss had already pulled a mask over his emotions, hiding them from Sans. It was done so quickly that the skeleton would’ve doubted the other monster’s desperation, had he not overheard it just seconds before in his voice, cracking under the emotion.

“Good,” The larger skeleton appeared to be completely unfazed, keeping his face totally blank. “You’re right on time.” The Papyrus turned away from Sans back to the third monster in the room, and the shorter skeleton’s gaze followed his.

The red soul in Sans’ chest nearly skipped a beat as pinprick eyes laid their sights on the last monster in the room for the first time, recognizing the turquoise scales on her face in an instant.

_It’s her._

Undyne.

**Notes for the Chapter:**

> ~Edited 4/30/17~  
> Out of the first four chapters, this one definitely went through the most rewriting. Both scenes ended in an entirely different way, and the Muffet/UF Sans dynamic is completely altered now. It's definitely for the best, as it'll allow me more room for UF Sans' character to grow from here on out. 
> 
> Hope you enjoyed~


	5. Chapter 5

It wasn’t the first time Sans wished he could be more like his brother.

Papy was strong and smart and confident. Even if at first glance he hardly seemed to look the part, that was the truth. Sans knew his brother better than anyone- he knew just how the other monster really was. And the younger skeleton tried to act just like him. But Sans couldn’t ever do the things Papyrus could. He couldn’t even come close.

Sans’ big bro could’ve easily gotten out of a situation like this. Pap would be able to overpower this twisted sicko in a fight with little to no difficulty. Yet more realistically, the larger skeleton would probably ignore the issue entirely, teleporting away in an instant.

But Sans couldn’t do either of those things, because he was Sans, and not his brother.

He didn’t share Papy’s innate and unexplainable ability of shortcuts, which seemed to bend the laws of time and space. And even after years of training with Alphys, Captain of the Royal Guard, Sans couldn’t make up for his glaring weaknesses in a fight.

He had exactly one HP. A number so low that a single attack from any monster would be enough to dust him _. Yet that wasn’t it._ Sans also had just one attack. An attack so powerless that Alphys actually let him use his full force during sparing sessions, while she handicapped herself by instead using a wood spear. _It didn’t end there, either._ Of course, Sans’ defense also shared the next-to-nothing number of one. Not like that mattered much- after all, no amount of defense could make up for his single HP.

His low stats had posed a challenge to him from the beginning, but it was at least a challenge the skeleton had been able to rise up to and meet. Sans’ weaknesses just meant he needed to fight better than any other monster if he ever wanted to join the Royal Guard. So he took it upon himself to do so.

The skeleton had learned to dodge attacks. He’d perfected a special blue attack, so he could catch enemies by surprise. Sans had trained, every other day, for years, just to work through his limits. He’d worked so hard to push past the boundaries that he’d been misfortunate enough to be born with- and he’d made progress. Slow and inconsistent progress, but progress nonetheless.

Now though… Sans stood alone in the bitter cold forest of some town that certainly wasn’t Snowdin, face to face with an angry skeleton who certainly wasn’t Papyrus. Here, the young monster couldn’t help but wish those statistical flaws of his hadn’t ever existed. With his single point stats, Sans was completely defenseless. So weak and exposed, with the other monster’s bone attack cutting into his neck and pinning the skeleton frozen in fear to the dark tree bark.

This was danger, right here. For what seemed like the first time Sans could recall, he was in a very real danger. Because all it would take the other skeleton to finish him off was one attack, and the look in the other’s eyes told Sans that the menacing monster wasn’t kidding around anymore.

 _A red attack._ Sans couldn’t decide if the adrenaline pumping through his soul and fear coursing through its veins was making his mind move too fast or too slow. His mind had been so busy regretting who he was and wasn’t that it’d taken the skeleton almost a minute to recognize the fact that he’d never seen a red attack before. He’d never even heard of one. It appeared to act just like one of Sans’ blue attacks, judging solely from the fact that it was jammed into Sans’ throat yet he was still alive.

 _If I don't move, I won’t get hurt._ Those were the rules of a blue attack. It seemed like this red was the same.

"Well?" Cold crimson eyes designed to intimidate glared into Sans' blue orbs, and the smaller skeleton’s eyes dipped to the ground to avoid the other’s gaze. “I told you I’d only ask once,” The bone pushed harder against Sans’ vertebrae as the other stern skeleton demanded an answer. He didn’t budge an inch, even as the magical attack began to scratch against the bone of his neck.

 _Where is my brother?_ The larger skeleton’s question rung through Sans’ mind. Of course, the shorter skeleton didn’t know where the other’s brother was. He didn’t even know where _he_ was. But obviously, this larger monster didn’t know that.

"Where?" The other skeleton’s voice rang out loud and clear, ordering the attention of Sans’ eyes. Piercing red pupils stared straight into blue ones, searching them as if they held the answer to his unanswerable question.

"...Who?" The skeleton finally forced out a response in a small, raspy voice that sounded just as weak and powerless as Sans felt.

"My brother," The larger skeleton’s reply was just as unhelpful as Sans should’ve expected. Red bone pressed even harder against the smaller monster's neck, and it felt as if Sans’ vertebras were about to be crushed under the weight of the attack. “Sans.”

 _That doesn’t make any sense._ He was Sans. How could there be another one? The pinned skeleton’s mouth hung open, the words he was searching for completely abandoning him. _Then again, I’m talking to another Papyrus._ An evil, angry, rapist version of his brother, nothing like the original, but still claiming to be the skeleton.

"I- I don't…" Sans tried to stutter out that his thoughts, but with the jagged end of the red bone cutting against him, he was finding himself a bit afraid of speaking.

"Where is he?" The larger monster was trying to come off as cold and emotionless as possible, but there was one thing he hadn’t pulled an emotional mask over. One feeling that Sans could see, displayed openly in the red, piercing pupils of the taller skeleton: Intense hatred and bitter loathing, seeping out of glaring crimson eyes, directed at _him,_ Sans, but not the Sans this monster was searching for.

"I... I don't know," The skeleton finally got the words out from under the watchful gaze of the other monster, choking on the words as he struggled to force them out. He spoke the truth, yet the second skeleton didn't seem to think so.

Without warning, the life-threatening red bone sliced across Sans’ neck, finally pulling away from the skeleton as its sharp point grazed over his bones, Sans having no choice but to resist the instinctive urge to flinch at the violent motion. Swiftly, the weapon was replaced with something just as strong and capable of ending his life in an instant: the dark red gloved hand of the other skeleton. The monster’s bony fingers wrapped around Sans' neck right over his blue bandanna, grasping the top of his spine a grip of steel. With just the flick of his wrist, Sans had little doubt this taller skeleton could snap his neck.

"What did you do to him?!" The fake Papyrus lost control of the emotionless façade he had moments prior, breaking out of the mask as he demanded what Sans did to his “Sans.” The anger was now written all over the larger monster’s face, his fangs bared with an unhinged expression as he shouted at the skeleton less than a foot from him. Yet beneath that, Sans thought he could sense something else… An emotion that he hadn’t seen under the larger monster’s mask. _Concern._

While the larger skeleton didn't seem keen on letting that fact on, Sans could just pick it up. The angry, vicious snarl on the larger monster's face and the biting tone of his words were just there to cover up the worry the other was feeling. Worry because of his brother. This “Papyrus” may have been messed up beyond belief, but he still cared about his brother.

Or is that just what he wanted Sans to think?

"I didn't do anything," The words he was looking for came much easier now. “There had to have been some kind of mix-”

"You fucking liar," Long, bony fingers squeezed tighter around Sans neck, and the smaller skeleton was happy for the thin layer of protection the blue cloth around his neck provided.  "You expect me to believe that you breaking into my house and my brother disappearing are completed unconnected?” The larger monster scoffed. “Bullshit,” It wasn’t hard for him to slam Sans’ skull into the tree. “Where is he!?"

"I don't know!" The physical abuse had left the short skeleton’s head ringing. He didn’t know what needed to say or do.  _Why won’t he just believe me?_

"If you don't tell me where he is, right now- without any more shitty lying- then I will dust you this very instant." The deadly serious glare on Papyrus' face told Sans that the other monster was in fact, very much telling the truth.

The panic was oozing out of Sans’ soul now, crawling through the skeleton’s bones. What could he do to make the other skeleton believe him? “I’m telling the truth!” Sans squealed, the tips of the pointed red gloves cutting into his neck with enough pressure to begin piercing the outer tissue. The shorter skeleton blindly pushed against the other monster, wilding flailing for his freedom. _Am I crying?_ His eyes were wet. And he felt so scared and afraid. He probably was crying. Though that didn’t matter, not now. “I don’t know where he is!”

"You expect me to buy that? That you don’t even have the slightest clue where he’s gone?" Sans could feel the gap between his feet and the ground widen as the taller skeleton lifted him higher against the tree. He kicked wildly, but still he couldn't break free. "You expect me to believe that, even though here you are, and Sans is nowhere to be seen?"

"Yes!" It had been what Sans had been saying the whole time, yet the smaller skeleton knew it was the wrong answer as soon as he opened his mouth.

For a moment, nothing happened. The shouting match stopped, and instead the taller monster’s red pupils only glared at Sans. The pair were so silent that the shorter skeleton swore he could hear his panicked soul pulsating in his chest.

And then the larger skeleton dropped Sans to the ground without a word, releasing his hold on him and letting the smaller monster fall onto his hands and knees on the ground covered with freezing snow.

Sans gasped in surprise as he hit the cold surface below him. He hadn’t expected the other “Papyrus” to let go of him. And even though he had, Sans still imagined that he could feel the lanky fingers digging into the bones of his neck.

"You're useless," Sans looked up to meet the other monster’s comment, but his only response was an involuntarily whimpered once he saw what lay before him. A storm of white bones floated behind the larger skeleton, at the ready. "I warned you what would happen if you didn't talk, didn't I?" He had, yes, but Sans hadn’t prepared himself for such a massive attack.

It didn’t matter, because before the young skeleton could cry out in fear, or beg for mercy, or even open his mouth to say anything, the murderous monster had already released his first attack.

 _Duck._ Sans had his natural instinct to thank for his life. The skeleton pressed his skull into the snow as far as he could. It was cold, yet not nearly as much as the chill that ran down his spine as a bone whizzed through the air above him, nearly grazing his skull. He could hear the sound of maybe a dozen bones stabbing into the pine tree behind him, piercing hard wood.  _Too close for comfort,_ Sans decided, knowing that his death had been less than a hair away.

Jumping up from the ground and pulling his head from the impromptu white bunker, Sans prepared himself to dodge another attack. It was a good thing he was too, as the second he was back on his feet, he was jumping out of the way of another flurry of bones.

 _Think Sans._ He wasn't going to be able to dodging attacks forever. Sans needed a way out of here.  _I can't scare him away._ The skeleton wasn't going to go away because of a few measly bones summoned on Sans' part. And if he couldn't scare him away with his attacks... then that meant Sans had to use them to actually _fight._

"Aren't you going to fight back?!" The Papyrus demanded as another set of bones were launched Sans way.

 _No._ He wouldn't be able to beat this monster in a straight up fight. Even Sans could see that it’d be suicide to try. Besides, he didn't want to actually hurt this Papyrus. That would be wrong. This other monster probably wasn't thinking straight. The Papyrus was probably just upset that he didn't know where his brother was. If they could just talk this out- 

 _Of course._ Sans felt stupid for not realizing it sooner. His blue attack.

If the smaller skeleton could get the Papyrus in another blue cage, he wouldn't be able to attack Sans anymore. That would force the larger skeleton to calm down and make it so the two of them could just talk this whole misunderstanding out reasonably.

Another attack of bones flew towards Sans as he began to pool together magic for an attack of his own. One of them cut through the left side of Sans' armor, tearing the material and exposing his ribs, as well as the light blue glow of his soul. _Not good._ Even his armor was no use protecting him against these attacks, the sharp bones piercing right through it.

Sans summoned the attack around the larger skeleton once again. Just like how he had done it in the living room this morning, a blue formation of bones surrounded the other Papyrus, effectively trapping him. The flood of bone attacks halted, and Sans sighed in relief, giving his body its first moment of relaxation since the other monster had shown up.

The other monster only seemed unimpressed. "This again?" He asked, snorting as he examined the cage.

Sans frowned at the larger monster. "I get that you're upset about losing your brother and all, but how about we talk this out- like, you know-  _adults?"_ It felt so weird to say something along those lines to a monster that looked almost just like his older brother.

Two red eyes stared at Sans with an odd expression, as if the shorter skeleton had been spewing nonsense as opposed to actual common sense. Honestly, how would this skeleton expect anything to get done at all if monsters just attacked each other like this? It would be nothing but pure chaos.

"See? This is better," Papyrus said nothing, only continuing to look at Sans with the same bored look on his face. "So, I get that you have a brother, and his name  _may_ also be Sans, and your name is Papyrus, which is a pretty big coincidence if you think about it, but-" Without a word the monster stepped forward, right through to confines of the blue cage.

"No!" Sans warned. Didn't he know that if he touched those, he would get hurt? "You're going to-" The words died in the skeleton's mouth as the Papyrus emerged on the other side of the cage, perfectly fine.

The shock took a moment to fully set in. Sans' blue cage attack was his strongest attack. It took a lot of magic and focus for the skeleton to summon it, and it definitely wasn't something he usually did, never mind twice in the same day. It had been one of the attacks Alphys had taught him to defend himself, a last resort when nothing else worked. The smaller skeleton had never been in a situation where he had been forced to actually use it. It was only for problems like... well, _this._ When a monster refused to listen to reason, and only seemed intent on hurting Sans. It had seemed like the perfect way for Sans to talk the problem out while being safe.

 _Yet... what can I do when the monster has so much HP, that the attack barely affects him?_ Sans really couldn't answer that question. When his best attack wasn't enough to help him, what would?

 _How could he have so much HP?_ Sans’ attack seemed to have barely affected the other skeleton. Not to mention, he must've used the same tactic to break out of Sans' _other_ blue attack, which meant even the combined damage of both of Sans' attacks didn't so much as leave a mark on the skeleton. No monster he had ever known had as much HP as that, as much as this Papyrus had. How was it even possible to have so much? 

"Ow," The monster sarcastically remarked, amusement apparent on his face as he saw the smaller skeleton's expression. He smirked evilly at Sans. "That sure hurt." Teeth grinded together as the frightened monster did the one thing he had put off doing until now. A check.

_* LV 6 - PAPYRUS – 62 ATK 54 DEF * The Captain of the Royal Guard. If you see this monster coming your way, run._

_Love._ The answer was so plain. So obvious that Sans should’ve been able to guess it since the other monster had tried to rape him in the house. The rapist was also a cold-blooded killer. Which made sense- both roles required some completely broken morals.

Suddenly the fearful skeleton found himself agreeing with the check’s warning more and more. This Papyrus had murdered so many, and Sans wasn’t intent on just being another number. _Time to run._

As the larger monster dropped his arm, letting loose a whole new attack of bones, Sans went with the gut feeling and didn’t turn back. Without another second of hesitation, the skeleton dodged underneath a nearby tree limb and ran, bones lining the spot he had just been in moments before.

Fortunately, the larger skeleton hadn't been expecting Sans to run away from him. It took the menacing Papyrus a good two or three seconds before he realized that Sans was making a break for it. However, the killer was quick to give chase, exploding into a full speed sprint after the smaller monster.

 _I've got to lose him._ Sans thought, hearing the larger skeleton running behind him. Sans had a good head start, but that wouldn't matter for too long. This skeleton was just as fast as himself, if not quicker, and his strides were nearly twice the length of Sans' own.

 _Where can I lose him?_ Surely there wasn't anything in this forest that would help him. All there seemed to be here was a seemingly endless maze of trees. _Maybe something in Snowdin?_ Sans had lived in the snowy town for years. Even if this wasn’t the version of the snowy town he was familiar with, it was close enough that he must’ve know of some way to lose this other skeleton.

 _The River Person._ Sans hadn't ever taken the hooded figure's ferry before. He always preferred to walk across the Underground. Though, if he could quickly cross the river, it would mean this Papyrus wouldn't have a chance to catch up to him. He could get to Undyne's lab in a quarter of the time it would take him to walk there.

 _Right._ So now the problem was just getting to the River Person. The bloodthirsty skeleton seeking for vengeance against Sans for something he didn’t do was gaining on him by the minute. Each time Sans stumbled over a log or stick, the other monster was able to pass by unfazed. He was quite a bit better at this whole chasing thing than the smaller skeleton, and while Sans shuddered to think why that might be, it still meant his precious lead was shortening by the second.

A bone went flying by the right of Sans' face, causing the skeleton to jump. He still had to dodge attacks too, even while he was running.

So he needed to get to Snowdin, as well as cross through the town to the River Person’s port. Sans felt kind of bad that he didn't know their actual name- it was rude to just call someone the "River Person"- but now was hardly the time for him to focus on manners.

Another bone flew across Sans' left side, cutting his pant leg, tearing the fabric. Papyrus was getting closer. Sans doubted he would be so lucky on the third attack. The next bone would most likely hit him, and this game of chase would come to an abrupt end. Along with Sans' life.

If he could just get a little more space between the two skeletons... a little breathing room. Sans hadn't dared to turn around and see how close the larger monster was to him now, but it was definitely closer than Sans would have preferred. He could hear the panting of the larger skeleton in his ear. The sound of his steps echoing Sans' own. But what could he do to give him more space?

The feeling of a gloved hand across his back startled the skeleton. Papyrus was reaching out, trying to grab him. And while Sans was  _just_ out of his reach, that would change any second now. If this Papyrus caught him, it was all over.

In a desperate, last ditch attempt to save his bones, Sans formed an attack of his own. A single white bone formed in his hand. It wouldn't do any damage at all to the larger skeleton, yet hopefully it would be enough to distract him.

Turning his head over his shoulder, just for a second, Sans could see the larger monster, just about on his heels. The determined look in the killer's eyes as he stared back at Sans. Papyrus' hand, reached out to grab the skeleton and hooking on Sans' blue bandanna. The smaller skeleton was hesitant to throw the bone, yet he did so anyway.

Tossing the bone at the monsters' feet, the larger skeleton tripped over it. Maybe it had just been luck, or the other skeleton had been so focused on grabbing the smaller monster that he hadn't seen it until it was too late. The skeleton began to stumble, losing his balance. Yet gloved fingers had already gripped around the cloth around Sans' neck, and they seemed intent to hold on tight. For a moment, Sans was afraid he'd go down with the larger skeleton. Instead, his light blue bandanna was pulled straight from his neck, untying in the skeleton's hand. The murderous version of Sans’ brother went down, tumbling into the snow with the blue cloth in hand.

Even though it had been a prized possession of Sans' for years, he had to keep going. Sans forced himself to resist the urge to go after the cloth, just like he resisted the urge to stop and make sure the larger monster was okay. 

"Sorry!" Sans called out, but the skeleton forced himself to keep on running. He had no idea how long the other would stay down, so he couldn't waste a moment. He turned his head back over his shoulder, facing forward.

As it turned out, the taller monster didn’t stay down for long. Only moments later, Sans could hear the scrambling of red boots digging into the snowy ground. Both relief and fear flooded over Sans. Relief, because the monster was okay- he hadn't been hurt too bad by Sans' attack or the subsequent fall- and fear, because the sound of swift footsteps meant the larger skeleton hadn’t abandoned his prey.

 _Snowdin._ The tree line faded into the open expanse of the snowy town, and Sans had never been so relieved to see any place in his life, despite the fact that it still was the darker and more desolate version of the Snowdin he was used to.

Yet Sans couldn’t allow himself a moment of rest. He wasn't out of the woods yet. Well actually, he was- but that wasn't what he meant.

The town square was still as empty as it had been before when the skeleton surged across the snowy ground. The small monster ran down the path beside Muffet's- or Grillby's- or whatever it was called, hoping beyond all hope that he’d bought himself enough time to make it.

 _The river._ Sans could spot the blue water a few dozen feet in front of him. And just as he had expected, the riverman was there too. It seemed almost as if he was the one monster that had managed to escape all of the weird changes the rest of the twisted version of Snowdin and its residents suffered from. The River Person was just as Sans remembered him, with a dark blue cloak covering him as he stood on top of his typical brown boat.

Not that any of that was much of a concern to Sans, though. All he could possibly care about was being safe. The young skeleton had already made it to the river and the other Papyrus wasn't even out of the forest yet, but that didn’t mean his little blue soul still wasn’t beating a million times per minute in his chest.

If the cloaked figure saw Sans, he made no move to acknowledge the monster’s presence. The River Person seemed perfectly comfortable saying nothing.

"Can I- _*huff*-_ get a- _*huff*_ -lift?" Next time Sans saw Alphys, they seriously needed to work on his endurance training. The skeleton was barely able to get his request out between deep wheezes. He _really_ wasn't used to having to run at full speed for such long distances, "To Hotland?"

"Twenty-five gold," The monster responded flatly.

"What?" Sans had never used the ferry before, but he was sure that it didn't cost anything.

"Twenty-five gold is the fare to Hotland," The riverman repeated with about as much interest as a monster watching paint dry.

"But I don't have twenty-five gold!" Sans exclaimed. His Papy- not the angry killer still chasing him around Snowdin forest- always told him to keep money on him in case of emergencies, but Sans was certain he didn’t have _that_ much on him. _Twelve gold._ Sans counted, patted down his pockets. _Not twenty-five._

"No fare, no ride," The River Person answered before returning to his earlier state of ignoring the skeleton.

"Please," Sans begged. "I'm being chased by a murderer!" No answer. "You really won't help me?" Nothing. _Unbelievable._ What kind of monster wouldn't be willing to help another in a situation like this? Sans needed another way to escape the larger skeleton- and quick. The rustling of tree branches across the path meant that the Papyrus had probably made his way out of the forest.

 _Yep._ Sans could see the red and black wearing skeleton on the other side of town. The vibrant blue bandanna he still held was a stark contrast to the rest of his apparel. Sans’ soon to be killer if he couldn’t find his way to safety hadn't yet spotted him, but it was only a matter of time.

 _How else can I get out of here?_ If he doubled back and tried to cross Snowdin, he could run to Hotland. But, Papyrus would definitely see him. And Sans wasn't too sure if he could keep running at that same pace through the entirety of Waterfall and beginning of- _Wait a minute,_ Sans’ thought stopped dead in its track as realization struck him halfway through his panicked train of thought. _Waterfall._  

He turned back to the River Person. "How about Waterfall? How much for the trip there?” Sans could feel his confidence wavering when the riverman failed to make an immediate reply. “It's closer, so it should cost less- right?" He wasn't sure if that was exactly how it worked, but it did make some sense to him.

"Ten gold,"  _Perfect._ Sans began digging around in his pockets for the payment. For a moment, the skeleton’s light blue soul flooded icy cold with fear, hearing the sounds of the second skeleton approaching rapidly. The other Papyrus had spotted him.

"Here," Sans forced himself to place the payment in the hooded figure's outstretched hand while half-stepping, half-jumping onto the boat in blind panic. Judging from the loud sounds of the footsteps behind him, coming closer and closer each second, the other skeleton was maybe ten feet away- best case scenario.

"It’d be really great if we could leave now!" Sans usually didn’t like ordering people around, but it was kind of hard to be polite while being chased by a monster fully capable of killing. However, the River Person didn't need Sans’ hurried request to tell him he was in a rush. The second the skeleton’s feet hit the deck of the boat it pulled out of the port and started on their way.

For a moment, Sans was afraid that the larger monster would swim after them. He froze as he wondered if he had made the right choice. The wooden raft was drifting slowly from the dock, and the skeleton felt like a sitting duck aboard it. One flurry of bone attacks in his general direction would end him; Sans had nowhere left to run or hide save for the few feet of boat he was left with. Yet fortunately enough for him, a quick glance back at the shore assured him that such would not be the case.

The cruel, killer rapist who claimed to be Sans’ brother stood motionlessly on the icy grounds of Snowdin, glaring soundlessly as the smaller skeleton floated away. The Papyrus wasn’t going to swim after him. He wasn’t going to summon yet another attack, nor was he going to start shouting at Sans again. Perhaps it was just dumb luck, or something that shorter skeleton had done had stunned the other into inaction, or there was some other simple reason that he couldn’t see, but Sans was safe from his menacing attacker. Instead, Papyrus’ lookalike said and did nothing, resigning himself to standing mutely on the shore as he clutched the light blue bandanna that he’d ripped from Sans’ neck by his side, bright red eyes gazing on watchfully.

* * *

The skeleton sighed in relief, letting out a breath of air he hadn’t known he’d been holding in as the coast of Snowdin and the antagonistic monster disappeared from his view. _Safety._ Finally. The boat ride provided the skeleton with some much-needed respite after narrowly escaping with his life. _I’m safe._ The words helped to comfort Sans, however true or false they may have been. _I’m safe._

Beneath him, his legs pulsated in pain. Sans had given it his all in order to escape the other monster, and he’d only just made it out in time. The skeleton collapsed onto the boards below him, hitting the wood with a soft thud. All Sans could do was focus on his heavy panting as he stared at the dark cavern ceiling above him, before sealing blue eyes tight.

He couldn't help but feel like giving up.

It was a new feeling. The lack of determination to do what was needed. Sans didn't usually fall victim to it, but this time was different. Despite his best intentions, he felt like giving up. Like just letting the sadness that had been building up inside take over and drown him.

Sans shifted the white sleeve of his undershirt to his eye sockets, using the tattered material to dry the wet pools that were beginning to collect there. It wasn't just losing the bandanna that made him upset. Sure, Sans had loved the blue cloth. It had been his main accessory for years, something he wore every day with his armor, his normal clothes, and even with his pajamas. It had been a gift from Papy when they had been younger, and Sans had loved it all the more because of that. No, Sans wasn't sad because he had lost that precious item of his. He was upset because of so much more.

He was a far way from home. That was pretty obvious. That Snowdin hadn't been anything like the snowy town Sans had grown up in. Everything there had been different. It had all been changed. The buildings, the monsters... all unlike anything Sans was familiar with. It was all colder, darker. All of it was completely unwelcoming.

 _Am I even still in the Underground?_ It was a stupid question, and Sans knew the answer long before his eyes were opened, meeting the cavern ceiling that had kept monsters Underground for centuries. The stars of the surface weren’t shining down on him. Instead there was the familiar glow of the shining crystals above: the main source of light in the Underground. Crystals the shined just as bright, whether it be day or night on the surface.

 _Is it just my imagination, or do they look darker than usual?_ Sans was probably just seeing things, but it seemed like the crystals didn't light up the caverns of the Underground as much as he remembered. Everything was darker, just like everything in Snowdin had been colder.

Sans blinked away the tears forming in his eyes, tearing his gaze from the ceiling above him. He was still in the Underground, but it wasn't the Underground he was used to. The skeleton couldn't explain how it was the case, but he knew it was true. This was some different version of the Underground. One where monsters weren't like what they were supposed to be. Where his Papy dressed in dark reds and blacks and was a murderer. And even though the idea seemed _impossible_ to the smaller skeleton, it was the only reality where any of this was _possible_. Because for what other reason would Paps be like… that?

 _Undyne will make more sense of this._ Even as he thought it, Sans couldn’t help but doubt himself. Why would this Underground's version of the Royal Scientist help him? Everything about this place was wrong. It had all been twisted and distorted until it was barely recognizable to the small skeleton. This Underground’s version of his brother was a perverted killer. How could he possibly predict what an Undyne from here would be like?

 _If I can just explain this all to her, she’ll help._ Sans had no reason to believe that was even remotely true. There was no logic to an assumption like that, but the skeleton felt it in his gut. Something told him the Royal Scientist was his key to fixing this. He was sure of it.

Sans glanced back at the cloaked River Person. The hooded monster hadn't said anything since they had left shore. The young skeleton wasn't used to monsters being so reclusive and unfriendly. He had thought that maybe the cloaked figure would at least try to make some small talk with him, but apparently that wasn't the case. Though, in a way, that was a good thing. At least it left Sans to his own thoughts.

Sans had no motivation to lift himself off the floor of the boat. His morning certainly hadn’t gone the way he had hoped, that was for sure. Besides nearly being killed by a murderer, he’d summoned his strongest attack twice, dodged way too many too close for comfort attacks, and been chased at full speed through Snowdin forest. And nearly been raped. _Yeah._ Sans sighed, letting his bones sink further into the uncomfortable surface on the boat’s deck.  _Can't forget that._

 _At least that’s behind me now,_ the skeleton told himself. He needed to be in high spirits.  _I'm close to going home._ All he had to do was cross Waterfall to Hotland, convince Undyne to build some sort of machine or science thingy to bring back his Snowdin and his Papy, and this would all be over.  _Simple._

The doubt pestering Sans' mind wasn’t so easily swayed. Part of him found it unrealistic that everything would be that easy to solve, yet the skeleton quickly pushed that pessimism aside, forcing himself to cheer up.  _High spirits,_ he reminded himself. A positive attitude was essential in situations like this.

The skeleton’s breathing had steadied once more, and he was starting to feel a bit more like his regular self. _The worst’s behind me._ Sans told himself, certain that it was the truth. If he just kept his positivity up, nothing would be able to stand in his way.

Sans unconsciously raised his blue gloved hand up to touch the base of his neck. The bare bone that his bandanna typically wrapped around felt so odd without the cloth covering it. His neck felt so exposed without it. The skeleton’s bandanna had been such an important item to him for so long; he could still remember when Papy had found it for him.

It had been back when it was just the two of them were all on their own in the Underground. The two skeleton brothers didn't have a house. Nor did they live in Snowdin. Actually, thinking about it now, they hadn't really  _lived_ anywhere. It was all kind of fuzzy to Sans, who hadn’t thought about it all in so long.

To the two brothers, the whole of the Underground was their home. It was like they were on a never-ending camping trip, day in and day out. Sans… didn't remember much from back then.

He knew Papy had taken care of him then. The taller skeleton had raised him. Pap… Pap had taken care of both of them. Sans’ big bro always acted so much more mature than his younger brother, despite the fact that he wasn’t even that much older than Sans’. Maybe it was because they didn't have much back then. All they had was the clothes on their bones, and nobody else to turn to, so Papyrus had stepped up.

A lot of their time was spent in places like the dump. Sans had always liked the dump. There had always been a lot of cool, interesting things to distract him from everything else. Sometimes there was even scraps of good food that the skeletons could eat. Or a mostly intact piece of junk that they could manage to sell for a few gold. The dump was where Papy had found the blue cloth.

The two skeletons had been shifting through different piles of trash when Sans’ brother found it. The blue bandanna could hardly be called that at the time. It was just some ordinary scrap of material, stained so dirty with dark smears that it was hard to make out what color it really had been. Other monsters, if they had seen it, wouldn't have given it a second thought, passing it off as another piece of useless junk. It definitely belonged in a pit of trash.

But not Papy. The larger monster took the dirty cloth from the trash heap he had found it in over to the cool waters of a nearby waterfall, while the smaller skeleton had been distracted with searching his own pile of hidden treasures. Papy had tried his hardest to clean it, running his thin, bony fingers over the dirty spots as water rushed on top of it. Then, once he had done the best job he could, Papyrus snuck up behind Sans, and without saying a word to his younger brother, he tied the cloth around his neck, fashioning it in the same style the shorter skeleton used even now.

Sans had loved it instantly. Despite the lingering unmistakable scent of rotting food and murky dumpster water, the younger skeleton loved the blue cloth. Sans could remember his brother motioning to the water below them, directing Sans' attention to his reflection, the younger of the two skeletons gasping in shock upon first seeing it.

 _I thought it'd go well on you. Plus… well, I know how much you like blue._ Those had been Papy's exact words, and Sans could remember them with perfect clarity. After the older skeleton had said them, the smaller monster could remember hugging his brother tight, screaming thank you, over and over again. His brother's response being only gentle laughter, as if it was nothing, but the larger skeleton could tell just how much it had meant to his brother.

For the many years after that, Sans wore it every day. No matter where they went. No matter how dirty the bandanna was, or how bad it smelled, Sans wore it. It continued to get more and more torn up, but he had never even thought of throwing it away. He had loved the gift from his brother, and he was never going to get rid of it.

And then he lost it.

Sans hadn't done it on purpose. It had happened years later, when the skeleton was old enough to help out with taking care of Papy and himself. They still didn't have any place to live at the time- only some makeshift camp on the outskirts of the Capital.

Sans had gone to Waterfall to wash some of Papyrus' and his clothes. It was easy to scrub the dirt off their old clothing with the cold waters of the rivers in Waterfall. But when the younger skeleton came back... he soon discovered that his blue bandanna wasn't with him. He had forgotten it while he had been washing the other clothes.

The second Sans had realized he had lost the precious item, he told his brother. Together, the two of them went back to Waterfall. They went to the river where Sans had washed everything... but the bandanna wasn't there. Sans could remember being so heartbroken, over something so small. But it wasn’t small, not to him. It had been his favorite. A gift from Papy.

That night, he had cried for so long that his brother had ended up waking up. Papy took one look at him before sighing. Without a word, his brother got up, kissed Sans on his forehead, and left.

Sans didn't go to sleep that night after that. Hours passed, and when his brother still didn't come back to the camp, Sans starting crying again, even harder than from the thought of losing Papy's gift.

He was afraid that his brother had been upset with him for losing his gift to him. Sans thought Papy might’ve even been angry with him. Sans had been worried that that was the case that he got up from their camp for the night and he stumbled around, searching for his brother. The young skeleton went all the way from the outskirts of the capital, through Hotland and Waterfall, to Snowdin, crossing almost all of the Underground.

Looking back, Sans couldn't even begin to piece together what could've made him think Papy had been angry. His bigger brother was never angry. He had never lost his cool, for as long as Sans could remember. And Papy had definitely never been upset at his younger brother. Sans had just been so young that he couldn't think straight, the fear of his big bro being angry with him blinding Sans from thinking logically.

When the young skeleton didn't find his brother anywhere, he had been in tears, convinced that his brother was gone, and he was never going to see him again. He had just been so worried, so afraid. So when he got to Snowdin, without finding a trace of the older skeleton, Sans' scared mind assumed the worst. That his brother was gone forever, and he was never coming back.

The funny thing? In the end, it was his brother who found him. Sans had been stumbling through Snowdin, lost, cold and in tears, terrified. Papy had found him, and without a moment of hesitation, he had picked his younger brother tight. Judging from the tears in Papy's eyes, Sans hadn't been the only one who had been crying.

 _Please. Don't ever do that again._ Pap had begged the younger skeleton between sobs. As it turned out, he had been just as upset at the idea of losing his brother as Sans.

The two of them held each other tight, neither one of the skeletons wanting to let go. When Papy finally did put Sans back down, the familiar feeling of blue cloth was there around his neck once again.

As it turned out, his brother hadn't been upset with Sans for losing his gift. He hadn't left Sans for no reason. The larger skeleton had instead searched the dump again, and he had found Sans' bandanna. Apparently, the current had carried the cloth back to the place it had originally came from.

Sans had felt so stupid that he burst out crying again. Of course Papy wouldn't abandon him. Papy loved him. Sans started apologizing for being so dumb, but Papyrus stopped him. Instead, his brother told him that it didn't matter, as long as they were together now. That everything would be okay as long as they were together.

And just like that, his brother had saved the day, and made everything okay. Like always.

"Why are you crying?" The soft voice of the hooded figure jolted Sans out of his thoughts. The startled skeleton looked over to the other monster, who had suddenly decided to speak up.

"I'm not..." The skeleton started to answer defensively, before hearing his own raspy voice and realizing that wasn't true. Two wet spots had formed on Sans face, each covered in fresh tears. He had been crying, even if he hadn't realized it. The skeleton sniffled and quickly wiped away the tears with his bright blue glove.

Thinking about that story again reminded Sans of how much he missed his brother. Of how much he wished Papy could be here with him now, to help guide him on his way through this different version of the Underground. But the hooded figure was still gazing at Sans curiously, expecting an answer.

"I'm upset," Was the only explanation Sans offered. The small skeleton really didn't feel like sharing the personal details of either his terrible morning or childhood memories with this stranger.

"That's it?" The hooded figure asked after a moment, seemingly expecting more from the other monster. _No._ Sans resisted the urge to add the fact that he had nearly been murdered and raped by some monster that looked just like and claimed to be his brother. He didn't want to say anything about the fact that he was stuck in some sick, twisted version of the Underground he was used to, or how he missed his real brother so much that he was revisiting memories from years and years before.

"Yeah," It was a lie, and Sans didn't feel right saying it. It wasn't right to lie, and not to mention rude. But it was also rude to be nosy, so the skeleton was able to justify it to himself.

"That's no reason to cry," Came the reply from the other monster. "Are you badly hurt? In extreme pain?"

 _Yes._ Sans wanted to say, feeling the aching of his bones. But he paused taking a moment to think about the other monster’s words. He was sore, and tired, and there was a profound pain in his chest. Yet was he in _extreme_ pain? Worse than anything he had ever felt before?

"No," Cuts and bruises were littered across all of Sans' body, marking up his white bones. But besides the slight stinging sensations of the cuts, he wasn't in pain. _The worst is behind me._ Just like he said before. The pain had been in a form of the humiliation of the larger monster molesting him, and the physical abuse he had been subjected to, yet that was now over. _The pain is behind me._

"Then why cry? If you're not in some horrible, awful pain, it could always be worse."

 _It could always be worse._  Sans took a moment to think it over. The rivermen was right. Yes, this whole experience had been unpleasant- or more aptly described as downright appalling. Today had been filled with the horrible, twisted stuff of nightmares. Consisting of nothing but close calls and near death moments, but it _could_ be worse. Heck, it could've gone a thousand times worse, in a hundred different ways. If any one of the other Papyrus' attacks had been slightly more to the left of the right, or if Sans had been a moment too late to dodge any of the bones, he'd be dead. His life... would just be over. A memory. And _his_ Papyrus, the brother that loved him so dearly, would have no idea what had ever happened to him.

If the fare to Waterfall had been more than the twelve gold in Sans’ pocket could afford, he would've been caught by the murderous version of Papyrus. Which meant he would also be dead. If the larger monster hadn’t noticed Sans wasn’t his brother, the skeleton would’ve been powerless to prevent the other monster from doing whatever he pleased. And if he had noticed the truth after assaulting the skeleton, Sans would _still_ die.

There were so many situations where things _could’ve_ ended considerably worse. In a way, the small skeleton was lucky. _No, lucky wasn't the word for it,_ Sans decided. If he had been lucky, he wouldn't be in this situation in the first place- because for as many situations as there were with worse outcomes, there were twice as many scenarios where things ended _better._ If Sans was truly lucky, he would home, in his version of the Underground, with his Papy. Safe, and happy. Like always.

 _Things are bad… but they could be worse._ Sans found himself agreeing with the River Person’s words. He was alive. That was good. He had escaped the psychopathic skeleton killer. Also very good. All he had to do was make his way through Waterfall to Undyne's lab in Hotland. This was the home stretch.

"Yeah," Sans whispered, feeling his usual optimism returning, replacing the fake positive mindset he had tried to force his mind into earlier. "It could be worse." The skeleton felt a bit better just saying it, knowing it was the truth. While this all certainly wasn't good, it could be worse.

"Told you," The River Person remarked happily, taking joy in hearing Sans agree with him. The skeleton forced himself to get up from the wooden planks of the boat. _No more moping around._ He needed to be ready to get on the move on once he reached Waterfall. If this Underground's version of Papyrus had traveled to Waterfall on foot, then he wouldn't be that far behind. And while Sans didn’t think that would be the case, he couldn’t be sure. Either way, if the skeleton kept moving he could stay ahead of his pursuer.

"Almost there," The riverman told Sans. It wasn’t long before the shore was in the shorter monster’s sight. In a few moments, the skeleton would be on his own again, on his way to Hotland.  _I can do this,_ Sans reassured himself as the boat began pulling up to the shore.

"Thank you!" He called out to the dark blue hooded figure before jumping off to the shore. The River Person only questioningly narrowed his eyes at Sans, as if the monster hadn't expected Sans to be so polite.  _Guess the monsters here aren't as well-mannered either, huh?_ Sans guessed, seeing as how the River Person acted as if it was unusual to hear the phrase.

The weight in Sans' pocket reminded Sans of the remaining two gold he had. "Oh yeah!" Papy had always told him to tip monsters for helping him. Even though the fare hadn't exactly been free, Sans didn't think many monsters took ferry rides with the cloaked figure. He deserved to be paid well. Plus, the riverman’s advice had been helpful; it really had cheered Sans up. Digging a gloved hand into the pocket of his torn black pants, he pulled out the remaining gold, two lonely coins. It wasn't much, but it was better than nothing.

"Here," The skeleton held out the gold in his hand. The other monster made no move to collect the it, only eyeing the money in Sans' hand with an odd expression. "Take it," He said, starting to feel awkward as he held his hand out, waiting.

Slowly, as if the other monster expected Sans to pull his hand back like some sort of cruel joke, the cloaked figure reached out to right below the blue glove. The skeleton turned his hand over, droping the gold into the monster's hand without a second thought.

"...Thanks," The monster's voice croaked out in disbelief, saying the word as if it was completely foreign to him. It was as if he had never gotten a tip before.

"Don't mention it!" Sans smiled. It was kind of amusing to see this monster's reaction to something as simple as two gold. The skeleton turned and started to walk away, before he remembered something else that had been bugging him.

"Oh!" Sans turned back to the other monster, who was still staring curiously at the gold he had been given. "I meant to ask, what's your name?" It was rude to just keep referring to someone as the "River Person" or the riverman. Sans knew he wouldn’t want anyone to call him “Snow Skeleton,” or “Guard Dude.”

"I am the riverman," Was all the River Person answered, pocketing his tip slowly. It was as if he was afraid something might happen to the two additional gold if his hand moved too quickly.

"No, what's your real name?" Sans pressed his question. The monster had to have some other name the skeleton could call him by, not just what he did. Another odd look came from the cloaked figure, as if Sans had asked some completely abnormal question and not something as simple as, “What is your name?”

"It doesn't matter," Sadness filled the other monster's voice, though for what reason, Sans couldn't tell.

"What? Of course it does!"

"No, it doesn't," The River Person gave Sans another glance over, as if he had only just identified the monster as some strange, foreign creature. "Take... take care of yourself, okay?" Worry and curiosity were mixed together into the River Person's voice. "It's dangerous out here."

 _Dangerous?_ Sans thought, not understanding the monster's warning. How could Waterfall of all places be dangerous? It was watched over by the head of the Royal Guard, Alphys herself. If there was anything dangerous out here, even in this strange version of the Underground, Sans was sure she would've put it away behind bars already.

 _She’s not the Captain here,_ the skeleton realized, remembering the check he had performed on the menacing version of his Papy. Apparently, that killer was the leader of the Royal Guard. Which meant that the Guard was probably just as much bad news as him. _What does that mean for the Alphys of this Underground?_ If she wasn’t the head of the Underground’s defenders, then what was she? The just and true warrior would never stand with something so corrupt. The Royal Guard was supposed to protect monsters. Not kill them.

The sound of the boat surging through the river once more tore Sans from his thoughts. Looking up, he saw the other monster and his boat leaving Waterfall without so much as another word.

"Wait!" Sans called out, yet the monster did no such thing. "What's so dangerous about Waterfall?" The skeleton stood hopefully on the shore for a moment, waiting for a response, yet the River Person didn’t even turn back to face him. The boat just kept on moving, until it disappeared form Sans’ sights. Apparently, the riverman thought the cautionary remark was all Sans’ needed to stay safe- any sort of explanation was pointless.

 _Get moving._ The small voice in the skeleton's head told him. If there really was something dangerous out here, he needed to get going. And besides, the sooner he got out of here, the sooner he’d make his way to Undyne's lab in Hotland and go home so he can put this whole thing behind him. Standing around on the river shore contemplating what the riverman had meant only delayed the short skeletal monster.

Slowly Sans turned around to see what was waiting for him. What greeted him was a dark, dreary corridor: his pathway to the rest of Waterfall. Uncertainly, the small skeleton forged forward into the dark. The panic in his chest was building up again, but Sans fought it back, beating it down with optimism.

 _I can do this,_ He told himself, though the doubt was still there, ever-present.  _No danger will stop me, the Magnificent Sans!_  The skeleton already escaped from a murderer today. Twice, actually. Nothing could stop him now. Besides, this was supposed to be the homestretch, right? _The easy part._

Sans' gritted his teeth in worry, his blue boots slowly edging their way into the darkness.  _So why does it feel like everything just got a whole lot worse?_

 

**Notes for the Chapter:**

> ~Edited 5/13/17~  
> One of the more minor edits. Dialogue and grammar cleanup is really about it.
> 
> Thanks for reading~


	6. Chapter 6

**Notes for the Chapter:**

> Just a little heads up- as for the actual placement of events in this fanfic, the Underswap Universe is pre-amalgamates, and before the creation of Temmie/Flowey. The story takes place before the Royal Scientist's failures, so US!Undyne might seem a bit more confident.
> 
> On the other hand, Underfell WILL be post-amalgamates and post-Flowey.
> 
> Either way, I hope everyone enjoys. Also, thanks to anyone who's commented! The feedback is always appreciated!

That morning had begun just like any other day in the Underground for the Royal Scientist.

Undyne had woken up early to run some weekly tests on the Core. It was essential that the machine that provided power to the whole of the Underground was regularly monitored. Dressed in her regular fashion- a white lab coat over a black top and blue jeans, with scarlet hair wrapped in a bun behind her head- the Royal Scientist had quickly made her way through Hotland and NTT Resort to the Core’s interior.

The tests themselves were fairly standard stuff. Check the ozone concentration of the Core to ensure sure production levels remain consistent, reassess the conversion of geothermal energy to magical electricity, complete a general survey of the machine for any structural damage… basic stuff, like she had said. It took Undyne just a few hours.

Following her weekly routine, the Royal Scientist brought her testing results to the Queen. Electricity production was fine and the ozone byproduct was of no immediate worry to Undyne, yet the acidic substance was still chipping away at the Core’s metal structure. Sooner or later they’d need to replace the steel sections of the building- a task which Undyne was not keen on dealing with.

Queen Toriel didn’t really care about the testing. She pretended to, though Undyne could see right through the act every time she droned on about ozone oxidizing metal in the Core. The scientist couldn’t fault the Queen for not being interested in complicated molecular processes. There was a reason a Royal Scientist had been appointed in the first place- so the Queen could focus on other pressing issues while Undyne tackled the scientific and engineering issues facing monsterkind. That lack of interest didn’t stop her from sharing the outcome of this week’s surveying, because in all honesty, the Royal Scientist suspected Queen Toriel enjoyed the company.

They pretty much skimmed over the topic of the Core entirely when they met. Actually, they pretty much skimmed over all the formal, work related discussion. Instead, the pair had enjoyed small talk over a slice of butterscotch pie. It was a… different work expectation than what Undyne had predicted when she’d first been appointed to the position, but not a disliked one.

The two of them always talked for about an hour or so. It was nice. It was always nice, because working for the Queen of the Underground had never been nearly as stressful as it sounded. Toriel never seemed to demand _anything_ out of Undyne. The Royal Scientist’s only assignment was to pursue advancements for the monster race, and to improve the lives of all the Underground’s inhabitants. That basically allowed the scientist absolute freedom over her research and experiments- with the added bonus of all the Underground’s resources at her disposal. That was the sort of thing scientists back in the Capital _craved._

By the time Undyne had made her way back to the lab, it was nearly noon. She fell into her typically lunchtime tradition- instant noodles, boiled in a pot over a single propane burner.

 _What to do today?_ The Royal Scientist thought between bites of noodles. _I could look into the human souls a bit more. A few tests could help me understand their behavior a bit more._ That was probably the only topic the Queen actually cared that the scientist researched. Toriel seemed to think that Undyne could use the six human souls they had now to break through the barrier, without a seventh. Maybe it was just naïve optimism, but the Royal Scientist thought the Queen might be on to something there.

Undyne didn’t exactly have much enthusiasm for the project, however. Human souls were complicated to deal with, and even more anarchic to understand. Toriel had lent her one for her studies, but it hadn’t been until recently that the scientist had made much progress with it at all. And the progress Undyne did make wasn’t exactly… hers.

She should probably explain.

Undyne wasn’t the first Royal Scientist. She… wasn’t quite sure who was, but remnants of their work seemed to be everywhere. The Core, the countless blueprints and plans scattered throughout the lab, written in undecipherable scrawling, and of course- the machine, left untouched for years in the middle of the lab’s lower floor. The current Royal Scientist wasn’t a fan of the machine’s design. It seemed unnecessarily disturbing, resembling the head of some… thing. Yet it worked. And that was the important part.

Undyne had followed the rough sketches left behind by her predecessor, along with some thorough guessing and checking to fill in the blanks the instructions left. She’d inserted the human soul into the machine, the “DT Extraction Machine,” and successfully used it to extract a mystery substance from the soul. Determination.

Technically speaking, the substance was cool as _heck._ It was a sickly red color, just like blood in all the human anime the Royal Scientist watched. Determination was thicker than water, resembling some sort of strange, viscous goop. It was like nothing the scientist had ever seen. Undyne could sense no magical energy coming from it whatsoever, but she still suspected that the red substance was behind the strength of human souls.

Now that she had it though, the Royal Scientist was at an impasse of what to do with it. As interesting as the stuff was, she had no clue what could be done with it. Undyne had theorized that it _might_ be possible, using the power from the human souls' determination, to amplify the power of some already existing power source, like… a monster's soul. But the scientist couldn’t be sure something like that would work. She wasn’t sure how she’d even test such a crazy idea.

 _So, I could do that… or I could ditch work for the day._ Undyne stabbed at her food with a fork, weighing the option in her mind. The idea was especially pleasing after forcing her mind to focus on the dreadfully complex topic of the human souls and their anatomy. And she couldn’t deny the appeal of hanging out with her friend Alphys for a day. The Queen surely wouldn’t mind, and the Royal Scientist had already fulfilled her obligatory survey of the Core.

Undyne and Alphys were even in the middle of watching one of the blue scaled monster’s favorites: Mew Mew Kissy Cutie 2. The first one, Mew Mew Kissy Cutie, had been an absolute piece of garbage, but the second was _way_ cooler, and Undyne had just convinced Alphys to skip the first one and jump to the second. Just the idea of the two of them watching it together made the scientist giddy with excitement. Work could wait, right? After all, it was just _one_ afternoon. It wasn’t like Undyne didn’t work late all the time.

Fate, as cruel as it was, didn’t care about the Royal Scientist’s desires. It had different plans for Undyne on this seemingly easygoing afternoon in the Underground. Plans that, depressingly enough, didn’t involve curling up on the couch with her mighty warrior crush and watching anime all day. Plans that involved another of Undyne’s friends.

**“Undyne.”**

The fish choked on a mouthful of noodles, nearly gagging herself on her fork as the other monster announced his presence. She had no trouble recognizing the voice.

"God Papyrus! I told you to stop doing that!" Barely getting the food down, Undyne turned to face the other monster. "It's not funny to sneak up on me like that!"

Any anger the scaly monster held quickly dissipated as she saw the look on Papyrus’ face. He had a dead serious expression, tainted with a startling sadness and full of raw emotion, something that the Royal Scientist definitely wasn't used to associating with the other monster. There were wet spots under his eye sockets, soaked with what Undyne could only logically assume were tears.

"Heh, sorry," Papyrus’ laugh sounded the exact opposite of how a laugh should sound. Awkward silence hung over the two of them like a blanket as the skeleton found the strength to say whatever it was he needed to.

"I need your help."

Undyne’s first instinct? Worry. Lots of worry. The skeleton standing before her wasn’t exactly the type of monster to look for help when things went south. Which meant something had to be _very_ wrong. “What? Wh- what is it you need help with?” The Royal Scientist choked the words out, her mind running through a list of all the things that might possibly be wrong.

"Sans," Papyrus' raspy voice seemed distant and unattached from his own body, as if the monster could hardly believe his own words. "Gone."

"Gone?" _That… that couldn't be right._ The other monster only nodded in agreement, too focused on regaining his lost composure to find the words to explain himself. Undyne's throat tightened. “Is he… _gone,_ gone? As in… you know…” _Dead._ What the scientist was trying to say was pretty obvious, even if she couldn’t bring herself to say the words. But the larger skeleton shook his skull in response, which allowed Undyne to breathe once more. Sans hadn’t been dusted. He’d just… disappeared.

"I'll- I'll call Alphys!" The solution popped into Undyne’s mind immediately. Ditching her half-eaten noodle lunch, she frantically searched for her cell phone. The Captain of the Royal Guard would be just as worried about the energetic little skeleton as Undyne was. And more importantly, Alphys would be able to find the skeleton in no time.

"I don't think she'll be able to help.”

"What- what do you mean?" Of course Alphys would be able to help, she had the whole of the Royal Guard under her command! The warrior could organize a widespread search of the Underground before Undyne could even finish her cup of noodles. Together, those royal warriors could find Sans faster than anyone else in the Underground.

The scientist found her cell phone hidden among the piles of paperwork piling up on her desk. Before she could do anything, however, bony fingers stopped scaly ones in their tracks.

"No," Papyrus reasserted, orange pinpricks staring intently at Undyne. "This is more of a you problem."

"A- a me problem?" Undyne stammered. She didn't want to be rude, but she hardly saw Papyrus' point. The whole of the Royal Guard was much better suited for a job like this- after all, what help could one scientist provide to a search? Having as many bodies searching the Underground as possible for the skeleton was what they needed to do, but Undyne was only one monster. She couldn't be everywhere at once.

 _Oh._  

“The cameras,” The Royal Scientist felt stupid for not realizing it sooner. She’d installed cameras across the Underground in order to monitor any threats. It was primarily a safety measure against any harmful humans that might fall into the cavern, but that didn’t mean she couldn’t use them to track the missing skeleton.

“Give me a minute, I can pull the feed up,” Undyne left the phone on the table and positioned herself over by the monitor, resting her hands on the controls before Papyrus could say another word.

"Undyne.”

"I've got it, don't worry!" A few keypresses later, a selection of all the camera feeds appeared onscreen. From Snowdin's main camera, the scientist could get a view of the skeletons' house.

"Undyne."

"Just- just give me a moment!" The footage began to rewind at Undyne’s command. "I'll find him- I'll find him." Was it weird that she sounded more panicked than Papyrus?

"Undyne," The scientist jumped once more at the sound of the skeleton's voice right behind her. She certainly hadn't heard the footsteps of Papyrus approaching. "I don't think your cameras are going to help."

She turned to face the other skeleton, confused. "I… I don't understand," Didn't Papyrus want her to find out where Sans had gone? Isn't that what he came here for?

"He's… he’s not _just_ missing," The skeleton said slowly, as if he was struggling with the words himself. "He's not even here."

 _Not even here?_ It wasn’t Undyne’s fault that she was confused, because the other monster refused to clearly _explain_ what the heck was going on. "Here… as in the Underground?” The other monster remained pointedly silent. “Papyrus?”

“Here as in this timeline.”

“Ex- excuse me?!” Undyne _couldn’t_ have heard that right. No, she was positive she hadn’t. Papyrus couldn’t seriously be suggesting that… no, that would be ludicrous.

“Sans is in a different universe.” Undyne’s ears hadn’t misled her.

“Back- back up a bit,” She doubted that she was getting the full story. “How can you… you’re sure about this?” The Royal Scientist couldn’t help but be skeptical. What Papyrus was claiming was absurd. There had to be some sort of mistake.

"I’m sure.” Undyne wasn’t used to the skeleton’s responses being so brief and no-nonsense. But given the situation, she couldn’t say it surprised her.

"How?" _How could Papyrus be sure? How could something like this happen?_ The scientist stared at the skeleton, waiting for _something-_ for _anything_ that might make sense of the skeleton’s claims. But the only response Undyne got was orange eyes, drifting off from her and fixating themselves on the large screen behind her.

Hesitantly, the scientist’s black pupils followed the other’s gaze, leading to the camera footage replaying on her monitor. Upon seeing what had claimed the other monster’s attention, Undyne immediately scrambled with her scaly hands to pause the video.

“Who is that?” There was an unfamiliar figure, sitting against the wall of Muffet’s; he was a skeleton, undoubtedly, and he looked just like Papyrus’ younger brother. Except he wasn’t Sans.

The mystery monster sat on the snow right beside the staircase before the bar. He looked about the same size as Sans, but instead of the silly (but adorable) “armor” the skeleton typically wore, this monster was wrapped in a dark black hoodie with a large white collar of fluff. His entire outfit was coordinated nothing like the blues, whites and blacks Sans always wore. Red eyes glared into the piles of snow in Snowdin’s town square with such intensity that Undyne genuinely wondered if the monster was attempting to melt them with just his gaze. Those murderous, blood red eyes were nothing like the innocent, gleeful blue eyes of the younger skeleton the scientist was familiar with.

“That’s Sans,” Papyrus’ answer came after the scientist had nearly spent a minute looking over the foreign skeleton. “Just… not the one we’re familiar with.” _This can’t be happening._ The scaly monster was starting to question the truth of those words. Because if what she was looking at was truly what it appeared to be…

“How?” The occurrence of something like this still dumbfounded the scientist. “If you’re saying that these two Sans…es somehow switched universes…” _Then that’s crazy._ “This is unprecedented." Neither monster seemed capable of prying their eyes off the screen.

"I know," The other skeleton didn't seem to care much for that fact. "This morning, when I woke up, Sans was gone. And this version of him had taken his place.” A sad smile crept onto his face. “Now do you get why I need you help?”

"You want your brother back," Undyne was well aware of the skeleton’s motivations. It was no secret to anybody just how much the older skeleton cared for his little brother.

The skeleton made no move to hide it from the scientist. "I can't do this alone, Undyne. Sans is in danger, stuck in another universe. I can’t stand to leave him like that.”

The scientist finally wrangled her gaze away from the computer screen long enough to glance at the other monster’s expression. Undyne saw the wet spots once again beginning to pool together with the skeleton’s eye sockets as he stared at the shining picture before him. She understood completely. “I’ll help.” The Royal Scientist felt an obligation to help her small skeletal friend out anyway. She’d be mortified if Sans got hurt when she could’ve done something to save him. “But I'm going to need something from you."

"Anything." The hoodie wearing skeleton would gladly sell his soul to save his brother.

“Tell me everything that happened, before this… swap. I want to know all the events that led up to it- anything that might’ve had some sort of impact on the timelines.” Undyne pressed a key and the monitor went dark, the image of the other Sans disappearing in an instant. The taller skeleton behind her had to blink away his surprise, as if he hadn’t realized how intently his orange eyes had been fixated to the screen. “We need to know what could’ve caused this to happen in the first place."

Papyrus nodded solemnly, and Undyne quickly pulled up a chair, turning her back on the cup of noodles that almost certainly were going to go uneaten now. She readied a pen and pad of paper. She decided to take notes; even the slightest details might prove to be instrumental to reversing this.

The skeleton launched into his retelling of the story without a moment of hesitation. He told Undyne about returning from his post at the day’s end. He told her about his weekly movie night with Sans, the homemade tacos they’d eaten and the movie they’d watched. Undyne had been the one to lend the film to the younger skeleton, but she decided to hold off on asking whether they’d enjoyed it until after they corrected the messy situation they were in.

And that was about it. After the movie, the pair had talked before falling asleep on the couch. There was barely the slightest deviation from their standard routine, yet somehow their night had ended in a cosmic anomaly: a switch between two monsters of separate timelines.

The next morning, Papyrus had woken up in the presence of a Sans that wasn’t his brother; with time, the skeleton had been able to figure out the involvement of the timelines. He had taken the other skeleton to Muffet's, where he’d explained just what was going on. Or at least, as much of what was going on as Papyrus himself understood.

Then the larger skeleton had convinced the second Sans to tell him about his timeline.

It was… a harsher universe than their own. That was for sure. An Underground filled with the worst kinds of monsters capable of committing the vilest of deeds. A parallel reality littered with pointless acts of murder, abuse… of _ownership._

It was a version of the Underground Undyne would never want to see for herself. And the fact that Sans was stuck there was somehow even worse. Someone who was so innocent that the scientist had never heard a foul word come out of his mouth, stuck in a place like what Papyrus described…

It was certainly a cause for concern.

“I can’t let anything happened to him, Undyne.” It was hard for Papyrus to find the words he needed. His throat felt dry and his eyes wet; the skeleton was fighting against another wave of tears that revisiting his worries seemed to have brought back. "We… we need to start working."

"Huh?" Undyne’s eyes jolted up from the pad of paper she’d written on. She’d been looking at the notes she’d taken on the skeleton’s story, but not really paying any attention to them. Had her mind wandered off in her worried thoughts? _Probably._

“We need to start working to correct this. Right now.”

“Ex- excuse me?”

“We can’t waste any time. We should head down to the lab now and get to work immediately.” Papyrus was so wrapped up in his little world that he completely ignored Undyne’s confusion.

“Get to work on what?” the Royal Scientist asked.

“Fixing all of this.” The tone of his instant response made it obvious Papyrus believed that much should’ve already been clear to the scientist. “You said you would help.”

“Well, yeah, but…” Undyne couldn’t help but be disorientated. Had she missed something? _You can’t just start “fixing everything” without a plan._ They needed to figure some things out first. The two of them needed to address the cause of this anomaly. And at the very least, that meant they needed to _find_ that cause. But they’d gone over the skeleton’s story and found nothing. _So what’s Papyrus talking about?_

“We’re losing time just standing here.” The larger skeleton seemed annoyed by Undyne’s inaction. “Sans has been stuck in that hellhole for at least a few hours now. If he’s in there any longer…” The Royal Scientist could hear the drop in the tone of his voice as Papyrus trailed off. “We need to get to work.”

“What _exactly_ is it you want us to get to work on?” Undyne wanted an actual answer, and not just the cryptic _“fixing all of this”_ response he’d given her before. “What’s your plan?”

For a moment, Papyrus made no move to reply. Orange eyes shuffled across the lab, seemingly meeting everything but the gaze of the Royal Scientist. Undyne opened her mouth to repeat her question, yet she found no need.

The sound of crinkling papers echoed from inside Papyrus’ front pocket; a second later, the skeleton’s ungloved hand emerged, grasping a stack of sketches. Without a word, the monster thrust the pile towards the stunned scientist. Uncertainly, Undyne started flipping through the papers. The pile was pages and pages of diagrams- blueprints.

“What are-”

“It’s a machine.” Papyrus was quick to answer. “I’ve… already got it figured out.”

“Is this…” _It is._ She didn’t even need to ask the question. The blueprints detailed a machine specifically designed to manipulate the timelines. Undyne had never before even entertained such an insane idea. Yet Papyrus clearly had.

 _There’s so many._ The Royal Scientist had never seen so many different blueprints for the same machine. Some were rough and simple drafts, seemingly hastily scrawled onto random pieces of paper after a breakthrough, while others were intricate and detailed diagrams, clearly thought out after many hours of attempts. “How did you… Did you know something like this was going to happen?”

Papyrus shook his head. “It’s… just a passion project.” Undyne didn’t hear the slight twinge of sadness, the sound of his voice cracking; she was too focused on the sketches.

 _How the heck is something like this supposed to work?_ Undyne couldn’t help but get flustered trying to piece the inner workings of the machine together in her head. The machine was second in complexity only to the Core. Yet even though the Core was complex, it was at least made _sense_. It was large and bulky, but it’s inner working were expertly designed and made perfectly logical. The machine that these sketches detailed, however… that was a different story.

The Royal Scientist doubted she could ever fully comprehend such an anarchic contraption. The separate mechanisms were connected in seemingly arbitrary places. The inner sketches of the machine were chaotic- a complete mess. The machine was all over the place- a lot of Papyrus’ diagrams even looked incomplete, as if the skeleton himself had gotten confused halfway through sketching.

Though what might’ve worried Undyne most was that in most of those sections, the ones Papyrus hadn’t bothered to complete, the skeleton had scrawled the word “magic.” No context. No explanation. Nothing that gave the scientist even the slightest clue what each mechanism was supposed to do. Just magic.

“You’re sure something like this will work?” The Royal Scientist knew she wasn’t too familiar with timelines and universes and the whole slew of theoretical implications their existence confirmed, but she doubted that correcting this anomaly would take only some generic magic.

“It will work,” Papyrus assured.

“How?”

“It _will_ work.”

“That’s not exactly what I asked.”

“I know,” Papyrus sighed. “ _Just…_ trust me on this one.” _Trust me._ Undyne could feel her soul squirming inside her as the words echoed inside her head. She had nothing against trust… but science needed more than faith.

“We can’t… I’m not…” The Royal Scientist bit her lip as she fumbled with the words. She could feel orange eyes staring right through her. “I’m not sure about this.” She set the pile of papers down on the nearby desk. “We’d have so much of a better chance to fix this whole situation if we could just _understand_ it first.”

“You think we have time for that?” Undyne was prepared for Papyrus’ aggrvation. Whenever a situation involved Sans and potential danger arose, the older skeleton had never been the most… reasonable.

“I think we’ll have to make time for that.” It was the Royal Scientist’s turn to purposefully avoid the gaze of the fuming skeleton.

“Time is a luxury we don’t have.” Papyrus’ gaze fell back on the pile of sketches he’d handed Undyne. He’d taken a shortcut from Muffet’s to his room to grab them before heading to the lab. "Every moment that we spend, lounging around, is another moment Sans is in danger.” The skeleton seized the blueprints from their resting place on the table, burying them back in his front pocket. “We _need_ to get working on the machine!”

“You’re not even sure if that machine works!”

“It will!”

“Prove it.”

“I… I can’t do that.” Papyrus’ voice cracked.

Undyne sighed. “I want you to answer me honestly.” She paused, waiting for Papyrus to look at her. “Do you know that this machine _will_ work?”

“Yes,” the skeleton responded without hesitation.

“One hundred percent?” The scaly scientist made it a point to stare directly at the other monster.

“…maybe fifty-fifty.” Undyne kept staring silently. “More likely thirty-seventy.”

“I take it that’s a thirty percent chance of success?”

“Yeah.” Papyrus wasn’t too happy to admit it.

“And what if it doesn’t work?”

Papyrus awkwardly scratched his arm through the sleeve of his hoodie. “Then-”

“Then we’ve wasted time building a machine that doesn’t work,” the Royal Scientist answered for him. “Then we’re back to square one.” Undyne couldn’t ignore the bitter taste in her mouth as she danced around what she was trying to say. “If we’re going to do this, we’re going to do it right. Sans is… There’s too much at risk for us to do otherwise.” _No room for stupid mistakes. No cutting corners._

“So… what are you suggesting?” Papyrus quietly asked.

“Huh?” The drastic shift in the skeleton’s attitude certainly threw Undyne for a loop.

“You’re saying that this machine is a waste a time. But unless you’ve got a better idea, it’s the best shot we’ve got.”

“I- well…” The Royal Scientist struggled to share her plan, thanks in no small part to the fact that she really _didn’t have_ _one_ , or at least, not one like Papyrus’. “If we find some way to observe the timelines and pinpoint just whatever had caused this, it’ll be much easier to build from there.”

“And how much time do you think something like that would take?” The skeleton’s irritation seemed to return just as Undyne’s uncertainty revealed itself. “Weeks, months? Years?”

“It’s… it’s hard to say.” The Royal Scientist massaged the hard lump forming in her throat.

“How long?” Papyrus pressed.

“…A while. At least a few months.” _If they were lucky._

“You’d leave my brother in a universe of killers for months just so you could have the chance to study timelines, observing and running tests, rather than building something that could actually help him?”

“Papyrus, that’s not what I’m saying and you know it-”

“Really? Cause it sure as hell seems that way.” The skeleton just seemed be getting more and more angry, and less and less reasonable. “I’m trying to save my Sans, but you seem to want no part in that.”

"Listen,” Undyne lowered her own voice, knowing she had to diffuse the situation before the fuming skeleton burst out in rage. “I get why you're worried. Believe me, I’m worried too.” She just couldn’t let that worry possess her, because than neither of them would be thinking straight. “I know you're terrified that something will happen to Sans. I… I know how important he is to you.” The scaly scientist tried her best to manage a small, comforting smile. “But... we need to do this right. If- if we don't, we're just going to waste even more time in the long run."

“…You’re assuming there will be a _long run._ ” Silence followed the skeleton’s offhand comment. There was no need to further develop his thought; both monsters knew exactly what Papyrus was talking about. _Sans, a skeleton with one HP, attack and defense, stuck in a parallel universe of murderous monsters._ It was a simple equation with just one blatant outcome.

"You might not think that Sans can make it on his own, even for a little while, but- but he can! I’m… I’m sure of it! He's been training with Alphys and- and he's gotten stronger! He'll be-"

"Don't you **fucking** lie to me," The already forced smile on the fish’s face fell flat as the other monster swore at her. "He's just a kid Undyne, and we both know his training has hardly been designed as brutal or ruthless like the monsters in that version of the Underground; they're goddamn cookinglessons! How the hell is that supposed to help a him survive a universe like- like that!?"

“Papyrus,” the scientist pleaded. “Will you just listen to-”

“No.” A stone-cold answer cut Undyne off. “I’m so _sick_ of you telling me what’s best for my brother. I’m the one who know what he needs. I’m the one who know just how much time he has, and it’s exactly how much time we have to solve this.” The skeleton left no room for the Royal Scientist to disagree.

"We need to get building now. Getting him back here is the only way he'll be safe. Sans can survive a day, but any more than that..."  _Don't._ Papyrus told himself.  _Don't finish that sentence._ He was already teetering on the edge of tears once more; thinking about his little bro being hurt was all he needed to push him over that edge.

"Papyrus..." Undyne knew the skeleton didn’t want to listen to a word she said, yet that didn’t change the fact the reasoning and logic were needed now more than ever. “You can’t do something like this in a day.” They were talking about breaking the laws of _time_ _and_ _space_. Such a feat was impossible to complete in one week, never mind a mere afternoon-assuming it was possible at all.

“Well we hardly have much of a choice, do we?”

“I…”

“This machine is our only chance. It’s our one shot to br-” The skeleton choked over his words. “It’s our one shot to bring Sans back.”

“It won’t work.” Undyne hated being so negative, but at least _one_ of them needed to acknowledge the reality of their situation. And since Papyrus was _clearly_ not that one, the task fell upon the Royal Scientist. “We’re missing so much here-”

“It has to work.” The skeleton shook his head, dismissing reason without a moment for thought. “It’s the only way.”

 _“Just_ _listen to me!”_ Undyne was exasperated. Was it just her, or did the two of them sound like broken record players, playing the same old sounds again and again, spitting out the same meaningless words and phrases to try and justify themselves? “What you want here: to cross universes and save your brother soon enough to be home for dinner; it’s impossible!” What part of that didn’t the skeleton understand? "You know better than anyone else it can't be done!"

"What else can I do, Undyne?" Papyrus laughed hysterically, orange tears pooling together once again. "I can’t just abandon my brother with some murderer! If I don't do this now, my little brother is going to-" The skeleton’s voice cracked as the overwhelming sadness that he’d been trying to shove aside for so long finally overtook him. "He's going to die."

The words were like a blow to Papyrus; he’d tangled dangerously close to the topic in his mind, but saying the words aloud made that feeling exponentially worse. Because saying them aloud made it _real._ The tears were flowing freely now, and the skeleton had no strength to stop them. "I need to save him, okay? I have to save him. Is that so wrong?"

 _…No._ The Royal Scientist sighed to herself. Papyrus wasn’t the only one being unreasonable. Sans was the most important thing in the older skeleton’s life. Most of the time, he was the only thing keeping Papyrus going. Sans was the reason he woke up every morning and went to sleep every night. To Papyrus, all that mattered was his little brother. And all he wanted to do was save him from an untimely demise at the hands of merciless killers.

In the end, Undyne couldn't blame him for that.

“No… you’re right.” Of course the larger skeleton would want what was best for Sans. _Why wouldn’t he?_ It was Papyrus. Had she somehow managed to forget that amid their argument?

"Please..." Papyrus wiped his tears away. He was still a mess, but that wasn’t a surprise. “I know it sounds absolutely absurd. I know that… scientifically, as well as logically, it seems impossible. But… this can be done. This machine _will_ work. It… it has to, because it’s the only way to keep Sans safe.” An orange sleeve swept away the last remnants of orange tears. “This can be done. I can feel it. I’m sure of it.”

 _No. No it can't._ Reality was overwhelming piled up against the skeleton's statement, and Undyne was well aware of it. It seemed that even Papyrus was aware of it, to a certain degree. _Something like this will never work._ It was unrealistic. There was no chance for a machine whose own creator predicted a success rate of 30-70, built in a day, with no proper plan besides half-finished blueprints.

“Please… just, _trust me.”_   _Trust me,_ the same words the skeleton had used no more than ten minutes ago; the same words that the scientist held a profound distaste for in the realm of all things science. “I can’t do this alone, Undyne.”

"...Okay," Undyne conceded. “We’ll build this machine of yours.” She still had her doubts; the skeleton had done nothing to dispel them. But that didn’t matter, because that was the point of trust, right? The Royal Scientist’s faith was in Papyrus’ hands. “I just hope you know what you’re doing.”

“I’ve got a better idea than you could imagine.” The skeleton smiled through his sadness, and Undyne couldn’t help but chuckle alongside him.

“You probably do.” She would never understand Papyrus and what he was capable of; the scaly scientist had given up trying a long time ago.

“I _definitely_ do.” The skeleton’s confidence was just what Undyne needed to soothe the worry in her soul. Even if he was joking, or even if he wasn’t, seeing him in a mood that loosely resembled his regular, lighthearted self was enough to ease the tight feelings in the fish’s chest. Shoving aside the stacks and stacks of doubts, a new sensation rose, taking the place of Undyne’s uncertainty. A feeling that convinced her that _maybe,_ just maybe, the scientist’s trust had been put in the right place; that the two of them might just be able to pull this ridiculous stunt off.

It was hope. Some may’ve called it naïve optimism, but it was just what Undyne needed to push her through what would most likely be another restless night.

The sound of automatic doors parting startled her, yet the skeleton before her hardly seemed to flinch. Two sets of eyes shot to the lab’s entrance, settling on the form of the newcomer.

 _Sans._ It felt weird saying his name in her mind; Undyne was used to associating the name “Sans” with an innocent and joyful ball of energy, and not this starkly different version of him.

"So you _are_ here," the words slipped out without Undyne meaning them to. She supposed the same was true for the gasp of shock directly preceding them. The scaly scientist had already seen the monster through camera footage, though somehow… this was different. It was like a splash of cold water, hitting her in the face, waking her up and solidifying the fact that _this was really happening._

Standing before her was tangible evidence of the multiverse theory, something that Undyne couldn’t have foreseen herself stumbling upon in her wildest dreams. Another Sans had been thrown into the place of their own, for some reason unbeknownst to all. It was utterly fascinating, and had they not been in a state of emergency, the scientist would’ve wanted nothing more than to run test after test on the foreign monster.

"Good.” Suddenly the larger skeleton’s seriousness was back; it took only a moment for Papyrus to make the quick switch from worry and grief. And Undyne thought it was curious, if not only because she hadn’t expected the weeping skeleton from seconds before to be so good at swallowing his sadness. _He’s a better actor than I give him credit for._

"You're right on time."

* * *

 

"On time?" The smaller skeleton stood awkwardly in the doorway, eyes trained warily on the unexpected familiar face. He had expected Papyrus; hell, he had been searching for the larger skeleton. Yet Sans hadn’t expected to see… _her._ "On time for what?"

"We're sending you back to your timeline,” the other skeleton announced, his voice just as emotionless as his expression. The desperation in the skeleton's voice that Sans had picked up from the other side of the door was gone, as if it had been hidden away as soon as he had entered the room.

 _Oh._ The skeleton resisted the urge to voice his disappointment. They were getting rid of him already, which wasn’t at all surprising. It was just… _so soon?_ It’d only been a few hours, and they’d already arranged to send him back to his Underground?

 _No… it’s fine,_ Sans told himself. He’d been preparing himself to go back ever since Muffet's. He’d known it was only a matter of time. The skeleton couldn't stay here. They didn't want him here, these monsters wanted their Sans. His presence wasn't wanted here.  _Nothing new._  

Sans forced himself to smile. "Sick of me already?" He was joking, but only partly. His soul felt broken in his chest, though the skeleton supposed that was his fault; if he hadn’t indulged himself with the impossible fantasies of this place, leaving would’ve been so much easier.

Papyrus just ignored him, turning back to _her_. She was wearing a lab coat, so Sans supposed that this universe’s version of her was the Royal Scientist. Or at the very least some kind of lab assistant. The skeleton’s instincts sided with the former. "We should get started."

"Yeah, right." She nodded. "You can head down to the lab and start on the machine, I'll just ask him a few quick questions.”

"Undyne.” Papyrus sounded as if he was warning the scaly monster.

"It'll just take a few minutes!" The lab coat sporting fish was quick to explain herself. "I promise. It doesn’t hurt to just check if he knows anything.”

“Just a few minutes?” The larger skeleton glanced between Undyne and the other version of Sans, seemingly torn.

“Promise.”

“Alright.” Papyrus sighed. For a quick second, Sans could see the exhaustion written of his face, buried within the orange eyes receded into the other skeleton’s skull. And then it was gone. “I’ll see you in the lab, then.” Without another word, the second skeleton dissolved into the empty air. And then it was just him and _her,_ the only two monsters remaining in the lab.

The atmosphere was stifling. Neither monster had properly introduced themselves; Sans had no intention to, and Undyne had never exactly been one to flourish in social situations. Instead they stood face to face for a moment before the scientist began to shift nervously on her feet.

“So- uh… hi.” The Royal Scientist’s awkward greeting did little to break the ice. She chuckled nervously as blood red eyes scanned over her wordlessly. Had she known what Sans was doing, breaking her down to nothing but a series of weaknesses and strengths, she would feel no more comfortable. “I’m-”

“Undyne.” The Royal Scientist hadn’t needed the skeleton to remind her of her own name, but she had hardly expected the other to know it for himself. “The Royal Scientist, I presume.”

“Well- yes, that would be me.” This Sans unnerved her, but she supposed that was by design. No monster lived in a universe like this one had without learning to give off a certain vibe of danger. “I’m guessing you probably know me- back in your timeline, I mean.”

“You could say that.” Sans left the open doorway of the lab behind him, feeling confident enough to allow the automatic doors behind him to close. It was clear this version of her was nothing like the Undyne he was familiar with. The Undyne in his universe was the ex-captain of the Royal Guard, turned cold, brutal murderer who slaughtered those who crossed her path with ruthless efficiency. Everyone knew about the deadly silent warrior who stalked her victims like prey, and no one was stupid enough to go anywhere near Waterfall, the warrior’s undisputed territory. It was just that Sans knew her better than most.

This Undyne seemed just like every other monster in this timeline: friendlier and less murder prone than what Sans was used to. She appeared to just be some sort of shy, nervous introvert. Someone who wasn’t all too good with working with other. In at least that regard, she was like the other Undyne, yet that seemed to be one of the few characteristics the two shared, meaning Sans had no trouble writing her off as a threat.

“Well if that’s that… I guess we could get started.”

“Get… started with what?” Sans still eyed the other warily as she shuffled off without warning. This Undyne was certainly no danger to him, but it took more than that reassurance to break years of hardwired survival instincts.

“I just need to ask you a few questions.” The scientist produced a paper and clipboard from her desk before sitting on her wooden chair.

"And why is that?" Sans wasn’t exactly used to being an open book. Today, he’d probably already answered more questions than ever before. He’d spent his morning pouring out personal details of his life to a version of his brother who he’d only met minutes before. Against his better judgement, Sans had told the skeleton everything he’d wanted to know; he’d told the Papyrus all about his kill-or-be-killed Underground and the merciless monsters who resided there. Sans had even gone so far as to give away to more… intimate details of his relationship to Boss. What else could these monsters want from him?

"Hopefully, if we can find some connection between your universe and ours, we can calculate the source of this..." The scientist paused for a moment, lingering as she waited for the right word to come to her. "...mix up."

"Exactly how do you suppose I’ll be any help with that? I don't know shit about science." It was the truth. Science was hardly popular among the monsters of his universe. It didn’t function as any sort of survival skill, and was therefore a useless; a completely fruitless pursuit. The only reason his Underground even had a Royal Scientist in the first place was because someone needed to watch over the Core and prevent another meltdown like the one that had happened years ago. Even then, the scientist, Dr. Alphys, would’ve commanded next to no respect, had she not been a psychopathic bitch with an obsession of unnecessarily cruel testing.

"Well- uh…” Was it just him, or had his swearing flustered this Undyne? _What is she, two?_ "…it’s possible that by comparing the events in your timeline to our own, this can all be… corrected."

“Exactly what is it you want from me?”

“If you could… walk me through the immediate details of everything preceding this swap, then I can compare it to Papyrus’ account.” _And then we just might get somewhere with this._ “Say… everything from about last night.” Undyne put on her best patient smile for the other monster as she prepared for the other to begin.

"...No.”

“Wh- what was that?” The Royal Scientist could feel the forced expression sliding off her face. She’d expected some resistance; this Sans had proved himself capable of such stubbornness already. What Undyne hadn’t accounted for was a flat-out refusal.

“I said no.” The skeleton had given away enough of his personal life for one day. Everything he’d already shared had been a mistake; a poor choice made in haste inspired by the confusion of that morning. There would be no more mistakes. The more of himself he could hide, the fewer of his vulnerabilities he’d expose. It was better to keep as much of himself locked away from the monsters of this universe as possible. Just like usual. “I’m not talking about this.”

“Can… can I ask why?” Had the situation been different, perhaps Sans would’ve found Undyne’s confusion amusing. It seemed genuine enough.

“No.” His answer left little open to interpretation. “No, you can’t.”

Sans didn’t want to talk about last night- not with the Royal Scientist, not with this universe’s version of Boss, not with anyone. In fact, Sans didn’t want to talk anymore about his _life._ He wondered if it even qualified as that. Probably not. Not after all the shit he’d been through.

At the end of the day, the skeleton was a piece of property, and Boss was keen to never let him forget that fact. That much was evident from the leather collar around his neck, tightened just enough that it was always in the way, always strangling and choking him, always constantly _reminding_ him of what he was. Some slave. Property.

Last night had been no different. In fact, last night had been better than most. And while he wasn’t proud of that… pride was somewhat of a foreign feeling to the skeleton at this point in his life- scratch that- in his _existence_. Sans hadn’t felt proud since… _well, that should speak for itself._ His reality was nothing more than a loosely connected train of regrets and amoral decisions, conducted by the one animal instinct still reigning supreme inside the monster: the constant drive to survive. Being alive was different from living, though the skeleton doubted that his soul still knew the difference after so long. He wondered if he’d ever known it at all.

What he’d done last night had been just one more regret; one more wrong choice in a line of unfortunate decisions that stretched from the moment he first opened his eyes to _now._ He’d committed himself to being Boss’ pet for the sole privilege of safety- or some sense of the word. He’d stuck to that role for years now. Not because he wanted to… but because that had become the only choice left for him. Suck the other skeleton off every once in a while, let Boss step all over him, and take the abuse without comment… or die.

Hey, Sans hadn’t said it had been a desirable choice.

So, he hoped the other monster could _forgive_ _him_ if he didn’t wish to share those private parts of his life, the chunks of existence that even he preferred not to dwell on. Especially not with a version of _her_ , of Undyne, a monster who’d played no small part in it all. Perhaps it was just a bit too _personal_ for him to want to share.

“You know that cooperating could make sending you back to your timeline much easier.” It was a laughably misguided attempt to make the skeleton talk. “I get that this… may be hard for you. Trust me, I know that talking about whatever it is you’ve been through might seem like the last thing you want to do. But… that’s exactly what I need of you.” Red eyes hardened in response, but the shorter skeleton mouth stayed sealed, much to the exasperation of the Royal Scientist.

“Papyrus already told me about your timeline, Sans… if that’s what you’re worried about.”

“He… he did?” Undyne nodded in confirmation. “O-oh.” _That shouldn’t surprise me._ Sans had already decided that telling anyone _anything_ was a mistake; this just proved that idea. It had been stupid of the skeleton to trust Papyrus in the first place. _Rule number one: trust no one._

“I know that it might be hard for you to talk about this, but I really do need your cooperation for this.” Undyne begged. “You can make this so much easier for all of us.”

“If he’s already told you everything, then there’s really nothing to talk about, is there?” The bitterness in his soul lingered in his biting tone.

“That’s not… this isn’t quite the same.” The Royal Scientist sighed, setting her glasses down as she buried her face into her hands. She sat in silence for a moment in a vain attempt to rub the tension out of her scales. Less than ten minutes of this and she was already exasperated. Working with monsters had never been her strong suit.

“Papyrus told me what your timeline’s like, but neither of us know whether something that occurred in your universe caused all of this to happen.” Undyne pressed the glasses back onto her face. “…That’s the goal of this: I’m trying to narrow down the probable causes for a universal anomaly like this.”

“So what?” The skeleton whispered the words beneath his breath. He wasn’t even looking at Undyne anymore; his red eyes seemed trained on some particularly special tile of the floor beyond the scientist.

“Excuse me?”

“I don’t care.” Sans’ disinterest was obvious, but then again, he made no move to hide it in the first place.

“But- but if you don’t help us, then we can’t get our Sans back- and we can’t send you back, either.”

“I don’t care,” the skeleton repeated.

Undyne bit her lip. It felt like she was talking to a brick wall, and the futileness of it all was taking its toll on the scientist. “Please.” Even to herself, her voice sounded weak. “I’m begging you-”

“Shut up.”

“I-” Undyne’s words failed her.

“Just shut the fuck up.” Sans wasn’t angry as much as just annoyed. “I’m not telling you a goddamn thing about my life.” The same went for the universe’s version of Boss, or anybody else smart enough to bother him. _They can all go to hell._

The pair sat in silence, neither monsters caring to look at the other; Sans’ red eyes kept their focus on the floor while Undyne’s found their place on the empty page in front of her. Without the skeleton’s recount of his timeline’s events, finding a cause for any of this was next to impossible. How could she compare the events of their timeline to the other universe when she didn’t have anything to compare Papyrus’ story to?

 _I can’t,_ she realized. _And I’m just wasting time trying._ If this other skeleton didn’t want to cooperate, then that was that; Undyne couldn’t make Sans talk. This skeleton was selfish and an asshole, nothing like the Sans that needed saving. He didn’t want to help Sans or himself; he didn’t care about fixing any of this. The Royal Scientist couldn’t afford to squander any more time attempting to persuade him to do otherwise, not when every second she spent was another very real moment the fate of her friend hung in the balance. Papyrus had a plan. He had blueprints. Undyne had decided to put her faith in him. There was no use in backing down now, especially when the only backup plan she had led to a dead end.

“Okay.” Papers found their way back to the desk as Undyne tossed them away carelessly. “Have it your way.”

“We done here?” Two pairs of eyes met, and in each set lied a sort of mutual annoyance.

“Sure. Whatever.” _Usually you’re supposed to start something before you can be done with it._ The scientist sighed before getting out of her chair. "We should head down to the lab."

"Isn’t… isn’t this the lab?" Undyne was already making her way across the room as Sans raised his voice to ask the question.

“Nope.” The one beat response echoed through the hollow “not lab” room. The sign hanging over the door outside seemed to have indicated otherwise, but who was Sans to argue with the Royal Scientist? She was the monster who ran the lab in the first place.

The skeleton had to double his pace to catch up to the second monster. Without warning, Undyne paused and Sans came to a screeching halt behind her. They’d stopped where the skeleton least expected: the bathroom door. It must’ve been one long trek to the lab if the scientist needed to take a pit stop before leaving.

Instead of entering the room herself, however, the doors parted automatically and the Royal Scientist motioned for the skeleton to move inside. Sans eyed the darkness of the new room warily. “I hate to break it to you, but this is a lavatory, not a laboratory.”

“Hilarious.” Undyne didn’t sound amused, _but_ _hey,_ Sans thought it had been good. The joke had apparently worn down the scaly monster’s patience, as she moved into the bathroom without another moment of waiting. The skeleton started to follow her, but his feet stopped in their tracks beneath the metal doorframe, his body involuntarily pausing as the full expanse of the room before him came into view. The little fish sign outside the door had led him to assume that this was a bathroom; Sans really wished that had been the case.

 _An elevator._ The control panel of buttons and labels positioned ominously on the wall opposite of the entrance was a dead giveaway that this room was, in fact, not a bathroom. _Lucky me._

The skeleton wasn’t a big fan of tight spaces. Elevators were known for being especially… _restrictive_. The close quarters nature of them meant they were a perfect place for an ambush against an unsuspecting target. And such little space left little to no room for him to dodge, either. Because of the skeleton’s special… _circumstances,_ that became sort of a big deal.

Of course, that had next to nothing with why Sans really hated confined spaces, but that was at least what he told himself.

“You kind of need to move.” The scientist deadpanned, jolting him back to reality. Undyne was standing across from the skeleton, next to the controls. She seemed perfectly undisturbed by the fact that the walls of the elevator were less than a handful of feet away from her on almost all sides. “You’re blocking the doors.”

“Ri-right.” Sans managed to croak the word out as his feet found themselves instinctively backpedaling away from the constrictive metal box, moving in the wrong direction.

“You need to be in the elevator, you know.” Undyne assumed the skeleton was making another joke; it was equally unfunny.

“I’m- I’m good.”

“What are you talking about?”

“I’ll just… stay up here.” The skeleton took another step away from the metal machine.

“Just get in here.” The Royal Scientist was getting more annoyed with every moment she spent in this monster’s presence. First, he refused to help by just answering a few simple questions, and now he was being intentionally stubborn for no other reason than being difficult.

_I prefer our Sans much more._

Sans said nothing. Instead, he could only respond by shifting his weight from one leg to another and back again. His lower body felt as if it were frozen solid, surrounded by large chunks of ice that pinned his feet in place through their sheer weight.

“I’m not leaving you up here.” The skeleton finally managed to force the bones below his torso to move, however unwilling. With small steps Sans pushed himself through the doorway, joining the irritated Undyne in the small metal room.

“About time.” The scientist didn’t give the skeleton a chance to double back. With a press of a button the door behind him slid shut, and a quick surge of panic engulfed the skeleton’s soul as his last viable escape route closed behind him, sealing him away in the darkness of a tiny metal cube _._ He tried his best to push the feeling down, with little success. It was hard to ignore the fact that he was in a box whose dimensions in feet was measured in single digits.

The pace of his breathing doubled almost immediately.

 _Relax,_ he told himself, but the word was wasted in his mind; it was impossible not to panic. It was impossible not to feel like he was trapped. The floor was starting to rumble beneath his sneakers, and the metal box encasing him was shaking. He felt like he was being smothered; his soul felt like it was being crushed. The walls around him were much too close. The ceiling above him was getting shorter every time he looked at it.

 _Relax._ The command flashed through Sans’ mind once more, in a futile struggle for dominance over his own emotions, yet it was no use. The sound of his strained breathing was bouncing off the walls around him as he leaned into the nearest one, clamoring for some sort of support. Everything was too close. Everything was getting closer.

 _Relax._ He wondered what being crushed to death felt like. Would he struggle against it? Would he scream as his bones snapped like twigs, or would his soul be shattered before he had a chance to open his mouth? _Relax._ Why had he gotten into the elevator in the first place? What had he been thinking? What had he been doing?

“Relax!” The word had stopped playing in his head and instead passed from the other monster’s lips into reality. It took Undyne, screaming in face, to help Sans realize that she had been the one repeating the phrase, in her best attempt to calm him down. He was shaking, he realized, and the walls weren’t closing in on him. They were just as close as they had been before.

“I didn’t realize you were claustrophobic.” Undyne said softly, suddenly understanding.

“Claustro-what now?” The elevator stopped and Sans couldn’t help but breathe an audible sigh of relief.

“Claustrophobic.” Undyne repeated, her annoyance miraculously cured and replaced with something resembling worry. “It means you’re afraid of small spaces.”

“I’m not afraid of anything.” Sans’ response came a bit too quickly. Admitting fear was a sign of weakness, exactly the sort of thing that left monsters exposed in his timeline.

“Oh, sure you aren’t.” The scientist seemed entertained by the skeleton’s defensiveness. “I suppose when you were quivering a moment ago, it was out of pure joy and not fear.”

“…”

“Don’t worry.” The door opened, and Undyne took the first step out. “I won’t tell Papyrus a thing. I’d hate to break the whole macho, detached loner thing you got going on,” she teased. Sans took a deep breath, shutting his eyes as he collected himself. He gave the scientist a minute to get ahead; he’d catch up. All he needed was a moment to himself.

When he emerged from the elevator, it was into a hallway that was still a bit too narrow for his taste. Undyne was waiting at the end of the passage with a small smirk on her face. They’d both forgotten their feelings of irritation with each other from before; Undyne was savoring the lapse in the impervious wall of emotion Sans had built up around himself, while he was busy recovering from his previous embarrassment.

“Are you ready, oh fearless one?” The skeleton found the other’s joy from his misery faintly familiar. It wasn’t as vicious and attacking as the harassment of monsters in his universe, but the mocking remained.

“Shut up.” The remark seemed to have much less effect on Undyne now that she’d seen another side of the skeleton.

“Right this way then.” The Royal Scientist led him down another passageway. Red eyes jumped from one thing to another, scanning the cracked surfaces with an arbitrary sense of urgency: Sans’ usual reaction whenever he found himself in unfamiliar surroundings.

Except this _wasn’t_ new. Something deep in the skeleton’s soul was resonating with this place. It was almost as if he’d… been here before. Which was crazy talk… _right?_

The narrow hallways Undyne led him down were a dark bluish green, lined with dark monitors. The walls were cracking under the pressure of the ground above them, and above them were pipes, undoubtedly old but somehow not yet rusted. It all seemed so familiar to Sans… but how?

“Bet you didn’t expect something like this, huh?” The hallway emptied into a wide room as Undyne misinterpreted the expression of confusion on his face. Sans should’ve felt a wave of relief; he was no longer able to reach either arm out and touch the walls surrounding him. Yet his mind was occupied with another pressing feeling inside his soul.

The duo walked through the wide room as Sans’ eyes glanced about, taking in everything there was to see. Undyne made her way across the area, yet his feet found their place in the center of the tiled floor, pinned to the spot by iron weights.

He _had_ been here before. The skeleton was sure of it. This wasn't just some wave of senseless déjà vu. There was something about this place that made something tingle inside of his chest. But just why… he couldn’t figure out.

"You okay?" The scientist had paused before the next door, looking back at the skeleton.

"...yeah," Sans lied. He didn’t like the idea that his own memories were failing him. Especially when something about this place felt so… significant. Surely there must’ve been some version of this secret lab in his Underground. Or was it like the workshop back at the other skeleton’s house; was this something completely exclusive to this version of his timeline?

For some reason… Sans didn’t think that was the case.

“You sure?” Undyne was concerned for the skeleton. Even in the larger rooms of the lab, it was still pretty cramped compared to the rest of the Underground. Despite her teasing, she didn’t want to cause the other skeleton’s claustrophobia to kick in again.

“Yeah. I’m fine.” The skeleton managed to make it sound much more convincing the second time around. “Let’s go.” He wasn’t going to share the details of his strange feelings of familiarity for this place. Not when he could barely understand them himself.

"Right." The scientist’s worry had not faded completely, but Sans pushed forward without another word. The pair resumed their journey through the nexus of halls.

They walked into a second elevator and panic gripped the skeleton’s soul momentarily, until Undyne walked out a side entrance of the tight metal box. Sans was hot on her heels at the exit, eager to put plenty of space between him and the constrictive cube. He found himself in a new hallway, where an empty doorway waited for the two of them at the end.

The door led to the twosome’s destination. Entering it, they found a pile of metal scraps that had been tossed into the corner of the room haphazardly. Papyrus was busying himself with examining the electrical wiring of some generator at the end of the room, but that didn’t mean the other skeleton failed to notice the two monsters' arrival.

"Well, you certainly took your sweet time, didn't you?" He said without glancing back at the other monsters.

"Yeah... about that-" Undyne nervously rubbed the back of her neck before being interrupted by Papyrus.

"I'm guessing you didn't find out why this happened, did you?"

"No." Undyne seemed to suddenly remember the outcome of her attempt. “He- Sans didn’t have anything to share.”

Papyrus only sighed and paused his working long enough that he could turn to face them. Orange eyes fell on Undyne, not even glancing at the shorter skeleton, instead skipping over the version of his brother as if he wasn't even there. "Told you it was a waste of time," A wrench flew across the room, encompassed in neon light. The scientist awkwardly fumbled with the tool, managing to catch it by sheer luck.

"Time to get to work,” The skeleton decided, ducking back down to inspect the electrical wires as Undyne walked over to join him.

**Notes for the Chapter:**

> ~Edited 6/12/17~  
> Very major edit here. Nearly every part of the Sans-Undyne conversation has been altered, and I've decided to add a few new plot points here for future development, including UF Sans' backstory with UF Undyne, his claustrophobia, and Papyrus' role in the machine.  
> These updates are taking a bit longer than expected, so I appreciate everyone's patience! Thanks a ton~


	7. Chapter 7

_It’s dangerous out here._ The riverman’s foreboding warning pounded in the nonexistent ears of the skeleton’s skull. _Take… take care of yourself, okay?_

It was a strange thought: Waterfall filled with danger. Sans held nothing but fond memories of the place. Especially when he’d been younger.

There was no place in the entirety of the Underground like Waterfall. Hotland was too dangerous to play near, with its dangerous cliffsides looming above boiling pits of magma. And Snowdin was too far from the makeshift camp the two skeletons had called home. The Capital was a crowded, bustling city which Papyrus had always preferred to avoid; the Ruins had been closed for as long as Sans could remember.

Yet Waterfall was perfect. Or at least… his version of it had been.

The soft sound of moving water was calming. The slow movement of the streams gave the illusion that the rushing water was in no rush at all. Even Waterfall’s namesakes managed to be relaxing; watching the shimmering water pour down sudden drops was a mesmerizing act.

When he’d been little, Sans had spent so much time in Waterfall that he’d memorized every corridor. After all, Papy had brought him there nearly every day. Before they had a home in Snowdin, the two of them spent most of their time in the dump. Sans would play with broken toys and scraps while Papyrus would rummage about the garbage piles for some salvageable junk worth a small price. Anything in relatively good condition could be sold for a few pieces gold for the pair to live off; the nearby shopkeeper had often bought things from him.

When the skeleton had first started to grow older, the two monsters had begun collecting a multitude of games to entertain themselves. Waterfall, with its safe surroundings and short distance from their camp, made it the best place for those games.

Perhaps San’s favorite part of the caves was that they were never too dark, either. Just like the lava in Hotland illuminated the cliffsides, and the white snow of Snowdin reflected the light of the crystals above, Waterfall was filled with the bright blue plants that lit up the caves like flashlights, and glowing rivers that shined as if they had been massive spotlights.

Combine that with the area’s soothing atmosphere, and it was no surprise that Waterfall had been the skeleton’s favorite place to be.

Though sadly, this version of Waterfall was not quite like the one Sans loved.

This reality seemed to be sticking to its pattern of taking everything the skeleton enjoyed and distorting it until it became unrecognizable. First his hometown and his own brother… and now the prettiest place in the Underground.

 _It’s dangerous out here._ The warning repeated itself in his head. The skeleton swore that the River Person’s words had driven him to the edge with paranoia; even a single droplet of water, falling from the cavern ceiling, would leave Sans paralyzed by fear.

He sighed, forcing himself along. _The sooner I get through here, the sooner I can get to Undyne’s and go home._ It was sound reasoning, yet the skeleton still found his pace drifting as he mourned yet another distortion of what he loved.

This Waterfall’s echo flowers were scattered across the land, few and far between. Their shine was no much better than the handful of drained crystals in the Underground “sky” above.

The rivers and streams the skeleton passed by were not a sparkling bright blue; instead, the water was a deep midnight cobalt color. The liquid still shone, but it’s glow was unsettling, shades darker than what Sans was used to.

In the unwelcomed darkness, the water’s slow flow sounded eerie, and not at all settling to the monster’s strained soul. The last thing Sans wanted to do in such place was explore the caverns’ depths, heading further into Waterfall while his soul protested that his feet were carrying him the wrong way _._ Despite that, the skeleton kept his feet and eyes on the path ahead as he forged onward through the corridors; corridors that remained dark and gloomy, no matter how hard Sans attempted to will them back to the bright blue caves he was familiar with.

 _Breathe,_ the skeletal monster hated that he had to remind himself of such a basic function. _Take it easy._

He’d like to think there was good reason for his panic. Sans wished he could say he was only afraid of whatever the riverman’s ominous notice foretold. After all, hearing another monster tell him he needed to make sure to “take care of himself” wasn’t exactly the most comforting phrase. Especially when paired with the cloaked monster’s warning. Yet that was not why his soul felt like it was being strangled by a tightening fear, grasping hold of the skeleton with an unescapable grip.

The reason for Sans’ panic was so much more juvenile.

 _It’s not even that dark…_ He tried to force his soul to listen to reason, but the rapidly beating heart wouldn’t budge. _Now’s not the time to be afraid of something so stupid…_

But that was the thing about phobias. Even in the most inconvenient of times, the fear remained present. It was not something a monster could pass up on if they chose to. Fear cannot be as easily discarded as a piece of garbage or a bag of trash.

 _It’s… not really a phobia._ Or at least, Sans refused to call it that. _It’s more like… a minor discomfort for the dark- really nothing major._ It was just… harder to see in the blackness… and- and Sans liked to err on the side of caution.

 _Yeah. That’s it,_ the skeleton told himself. _Not afraid, just… careful._ One could never be too vigilant of the dangers hidden in the dark; that was perfectly natural.

It had never been too much of a problem back home. The Underground he knew was always shining bright, day or night. Especially since there was no physical difference between the two. Buried beneath the surface, there was no sun or moon to dictate such things. The Underground remained just as bright and well-lit in the morning as when Sans put his skull down to go to sleep at night. Total darkness was rare, if not completely nonexistent.

But here… _it’s all so much darker._ Just another reason Sans desired to be home as soon as possible. It was just unfortunate that getting home meant making his way through the dimly lit corridors of this Waterfall.

The skeleton tried his best to not stray too far from the light. He stuck close to the small pockets of bright that echo flowers brought, and he took some small comfort in the bubbles of dull light that came with the slow-moving rivers that crossed Sans’ path, even if they stretched only a few feet before fading back into shadow. Undyne had once told him there were tiny, microscopic plants floating in the liquid- plants with the same genetic makeup as the echo flowers. The scientist had explained that was why the water glowed.

 _I think they’re called algae. She said the light’s due to bioluminescence… or something like that. I’m not really sure._ The skeleton found that taking his mind off the worrying situation he was stuck in made him feel a bit better. _I guess there’s less of them here. Which would explain why it’s so-_

Dark.

Sans’ line of thought was hitched on the one topic he’d wished to avoid. The paradox was that while focusing on something other than the pitch blackness of the unlit caverns meant that he could at least partially ignore his _slight_ distaste for the darkness, it was impossible to concentrate on anything but the void surrounding him.

 _Ironic that the only time my mind refuses to wander is when I want it to…_ The skeleton complained to himself, hurrying along on his path. _Kinda funny, considering how often I’ve caught myself doing it._

As Sans continued onward, his footfalls echoed softly through the corridors of Waterfall, his mind tuned in solely to the pounding in his chest and the darkness smothering him. It was hard to tear his mind from his fears; ignoring what the monster saw as a threat completely abandoned any sense of self-preservation.

The skeleton turned a corner from one cave into another narrow corridor. It wouldn’t be too long now. As far as Sans could tell, the two incarnations of Waterfall still mirrored each other location-wise, despite their drastic differences in atmosphere. The skeleton remembered a cavern just like this one back in his Underground, relatively close to Waterfall’s exit.

A lonely echo flower sat in skeleton’s path, its petals drooping off to the side. In spite of the flower’s dull shine, which could not compare to the bright echo flowers back home, the light blue plant was still comforting to Sans

Moving towards the light like a moth to a flame, the skeleton approached the flower. A small smile crept to his face as the warm, fuzzy feeling of safety engulfed him. Just as quickly, a memory of times past crept into the monster’s mind. He’d said that he and Papy had loved to play games when they were younger. They’d had tons… but Sans’ favorite game had involved the echo flowers.

It was simple; Paps would leave a message on one of the blue plants for Sans to find on his own. Sort of like hide-and-seek, except the seeker was looking for an echo flower and not another monster. It had always been fun. Much more fun than Sans’ explanation was making it seem, to be sure. _It was just- it had always…_

Most of the larger skeleton’s messages were silly jokes. Things that would never fail to produce laughter from the younger monster. A few were endearing remarks his older bro made lovingly. Sans took lots of comfort in those. And… and some even managed to be a cross between the two.

 _We… we should play it when I get back._ The skeleton’s smile faltered for a moment, cracking under his realization. _We… we don’t play games anymore._ Sans hadn’t even thought about their hide-and-seek styled game since the last time he and Papy had gone to the dump to look for scraps. _Which has been years now._

Those were the only times they ever played. Pap would go leave a message on an echo flower within calling distance of the dump, and Sans would go off exploring as his older brother searched for something that might be worth a meager amount of gold to the nearby shopkeeper.

 _I don’t know why that is._ Was it because he had grown up? Did Papy think he was too old for games now?

 _…am I?_ If that truly was the case, Sans was sorry, because he missed _that._ Those hours he’d spent, prodding the reaches of Waterfall for echo flowers he’d yet to discover, finding secret cracks and crevices along the way. All those days he’d run back to Papy, bustling with excitement because _he’d found it!_ And all those days he returned pouting, because he had yet to. Every time that happened, his big brother would give the same response:

“I’m sure you’ll find it tomorrow, bro,” he would say, lightly kissing the top of Sans’ forehead. There would be an audible clink of bone, meeting, and Papy would hold his place there for a second or two, before pulling away and patting the other monster’s skull. “I believe in you.”

 _I believe in you._ It wasn’t hard to imagine those words coming from his brother’s mouth now, encouraging Sans to move forward. Yet instead the skeleton remained rooted in place, staring teary eyed at an echo flower as his mind played old memories of childhood fun.

 _I miss that._ That feeling of closeness. That sensation of inseparability. Sans could remember almost nothing from that time in his life, yet he knew one thing for sure: he and Papy had been especially close then. They’d been by each other’s side, day and night. They never went anywhere without each other, and the fact that their little game of echo flower hide-and-seek was the one time Sans could remember not being alongside Papyrus spoke volumes of their intimacy.

 _We had nothing..._ No house to live in, no roof to sleep under, no work, which meant no gold, which in turn meant no stable source of food; the skeletons had no other family and nowhere to go. They were without anyone to turn to… _But we’d had each other._

 _I guess it never registered with me how bad we had it, huh?_ Yet then again, even all that seemed better than the situation he was now in. _The poverty, the uncertainty, the hunger…_ He’d trade it all back if it meant Papy could be with him now, in this strange, foreign place that pretended to be the Underground Sans’ knew.

 _I just want him._ The skeleton wanted him here, now, with him. His big bro was all he needed to make everything feel okay. He didn’t need to be back home; he just needed Papyrus. Because at the end of the day… Papy was his home. Home had nothing to do with a house or a place or a community. Paps was the only home Sans had ever known. He was the only home the skeleton wanted.

 _Look at me, getting all cheesy._ A drip of water hit the ground before the echo flower, soaking into the coarse soil below, and it took Sans a moment to realize it wasn’t another droplet falling from the cavern ceiling. _It’s been only a few hours, and I’m already crying over him._

But it really hadn’t just been a few hours. It hadn’t even been only a few days, or months. He wasn’t that oblivious. The skeleton knew it had been so much longer than that.

 _Our attachment to each other ended years ago._ Yet “ended” wasn’t the right word, was it? An ending implies a definitive point of change. _Our inseparable bond was cracked and weakened with time._ The separation had been slow, not sudden; like a stake being driven into a soul under growing pressure, plunging marginally deeper into the soft tissue with each ounce of weight pressing upon it. The slow process meant it had been so much harder to recognize the change. Until looking back.

But there _had_ been a change. That was undeniable.

There was a point, where they’d been so much more than what they were now. A time when the two would share every minute in the other’s presence… rather than seeing each other once or twice on a regular day.

Now, movie nights were the only time Sans got any _real_ interaction with his brother. _Sad, isn’t it?_ They’d chat idly in the mornings over breakfast and Papy would crack jokes on their way to their posts… but the skeleton always got the feeling that he wasn’t really there. Which seemed silly, thinking about it, but it was the only way Sans could describe it.

Most afternoons and nights, the two would barely even see each other. Every other day, the younger monster would go train with Alphys after his guard duty. Papy would head out to Muffet’s, where he often stayed into the wee hours of morning. And if that wasn’t the case, the older monster would spend his nights buried in his room behind the house, where he might as well have been dead to the world.

 _I miss my brother._ Sans missed the skeleton who would do everything alongside him. The monster who would make up games and find ways to distract Sans from their problems when they’d been young. The monster who would set up puzzles with him in Snowdin and make all his fears and nightmares disappear with a simple hug. Sans missed him not being here, when he could use him most. And he missed the old bond that had waned.

Sans and his brother were still close, obviously. Very close. After all, the pair lived together. They shared morning meals together; the two spent a night every week watching movies and cuddling on the couch together. _Plus, brotherhood’s a bond for life, right?_ It wasn’t exactly like he would ever have another. Papy was Sans’ best friend. And Sans was his. He doubted anything could ever change that.

 _Now I’m getting all sentimental._ The skeleton wiped the tears from his cheeks with his gloved hand. The cloth material dried the wet spots quickly. _This wasn’t exactly what I had in mind when I asked my mind to wander._

 _Guess I kinda got ahead of myself there, huh?_ The skeleton looked back to the echo flower in front of him. His thoughts had distracted him from the mission on hand; for a short while, he’d completely forgotten where he was.

 _I should focus._ The beat of the skeleton’s soul had found a reasonable pace in the comfort of the flower’s light, but he needed to get moving. _I don’t want to stay here any longer than I need to._ His mind had strayed to different issues that he was in no place to deal with right now; it was best to focus on what little he could fix.

The skeleton stepped forward, ready to move past the plant standing in his path. However, his pace faltered under curiosity as Sans wondered what an echo flower in this version of Waterfall might have to say. There was no harm in a quick listen, now was there?

Thanks to his stunted height, the skeleton barely needed to crouch. Moving his head beside the plant’s bright blue petals, he held his breath, listening for the echo flower’s message. It took a few seconds of silence before Sans realized there was none.

The silence was eerie and new. Never before had the skeleton experienced a soundless echo flower before. It was unsettling. Most flowers picked up their first message before they’d even fully grown, but this one had not. No monster had ever whispered a comment into this flower. The plant had never picked up on any passing conversations. It had heard nothing but silence, all it’s life.

That needed to change. The skeleton took a quick second to think about what to say. He decided to keep it simple.

_Hello! Hope you have a great day!_

Sans backed away as the message repeated itself softly through the Waterfall cavern. He frowned. It wasn’t… great, per se, but it sure was a lot better than silence.

_Hello! Hope you have a great day!_

The skeleton sighed as the phrase repeated. It certainly seemed… underwhelming. Yet then again, Papy’s messages had always been better. His brother always seemed to know exactly what to say; his words never failed to do what they sought to.

Thinking about Papyrus, an idea burst into the skeleton’s head- or rather, a memory that sparked an idea. As he leaned forward, the words began to pour from his mouth to the echo flower’s petals. Sounds and syllables combined to form one of his brother’s jokes. To Sans, it seemed like the perfect fit.

_Why couldn’t the gardener plant any flowers? Because he hadn’t BOTANY._

This time as the skeleton backed away, a smile had painted over his face. He wasn’t saying that he _approved_ of the pun. After all, he’d never hear the end of it if Papy knew he’d shared one of his jokes. It just… felt right. There was so much doom and gloom here that any sort of joke ought to do good to cheer some monster up. A little light in darkness was never a bad thing, right? Even if it _was_ admittedly cheesy.

Finally, the skeleton moved past the echo flower and onto his path. He had to get moving sooner or later; it was just unfortunate that meant walking once more into the blackness.

 _Not far now,_ he assured himself, fighting the beginning of panicked constrictions in his chest. _Not far to Undyne’s._ He’d get through the corridors of Waterfall and make it to Hotland. Then it would be just a short stroll to the lab and a little convincing to win Undyne over. And then Sans could go home. To his Underground, to his Papy, and to his friends.

If the River Person was right about anything, it was that this could be much worse. He was in a relatively good place now, compared to the storm of trouble his morning had stirred up. _Just need to stay optimistic._ That was the key to making it through this.

After what felt like an infinity of darkness to cross, the skeleton’s feet finally found what they’d been searching for: solid wood. He’d made it to the old bridge by the end of Waterfall, and what was more, his stroll had been completely uneventful. It seemed the riverman’s final warning had been unnecessary. There was nothing for Sans to worry about in Waterfall.

Crossing the creaky bridge lead the skeleton into a larger cave, where cavern walls were stripped away to reveal what the skeleton had been searching for since the moment he stepped foot out of Snowdin.

 _I made it._ He was so close now that he could identify the towering mass that was the Core. And he could see the dark red hues of glowing Hotland lava a short distance away. Sans was right at the exit to Waterfall, where sharp, pointed rocks formed the cave entrance into the next area. One last cavern, and he’d be in Hotland. Even his phobia stricken soul felt a wave of relief hit alongside the realization.

The skeleton smiled. For once since arriving in this distortion of the Underground, it seemed as if things were looking up. _Not too long now._ Not too long before he’d be home, with Papy.

How stupid of him to think that he was okay. Especially when things can turn from okay to not even the slightest bit in the blink of an eye.

Hurrying along into the final cave, Sans felt invincible. The pale red glow at the end of the tunnel saved his soul the strain of finding his way through a black void of emptiness once more. Yet once the skeleton’s blue boots hit the ground inside the cave, a strange transformation seemed to take effect.

 _Huh?_ His pace slowed to a crawl, before halting altogether. Sans looked down, but it was still too dark to make out exactly what it was. It seemed as if the ground itself had changed under his boots. In a few feet, the surface had shifted from the coarse soil that filled the rest of Waterfall- the sort that made a solid crunch with each step- to something… unfamiliar with the skeleton. _Weird._

The new substance was soft and unstable, as if it hadn’t quite settled in place. It padded Sans’ footsteps, making them sound completely silent. It was almost like… sand.

 _But there’s no sand in Waterfall._ At least, not his Waterfall. Without hesitation, the skeleton reached down to investigate further. His glove scoped up a handful of the sand-like mystery substance. It smudged into the blue cloth- quickly proving itself not to be sand- though that only strengthened the monster’s curiosity. He brought the pile closer to his face, where he could see it better.

 _Gray?_ Sans glanced at the substance once more, checking to make sure he’d correctly identified its color. _I’ve never seen gray sand before…_ Even as he thought it, the skeleton’s mind was working to put the pieces together. Gears were turning in the head of the naïve skeleton, trying to find some answer for his confusion.

It’s just a shame the answer was what it was.

 _Oh._ The gray powder slipped through the empty slits between his fingers as Sans’ hand loosened its cupped hold. As naïve as the skeleton was, he was not a complete fool.

 _Dust._ Not the kind that settled in areas after prolonged periods of disuse and no cleaning, either. Dust: the last remains of passed away monsters. The fine gray powder pressed into Sans’ now dirty blue glove could not possibly be anything else.

He was standing amidst a graveyard of monster remains; dozens- if not hundreds of monsters, dusted in the same spot, in the same cave that bordered Waterfall to Hotland. The fact that the disintegrated corpses of so many had collected in one place…

That was surely no coincidence.

The skeleton’s body went rigid, legs frozen like stone pillars in the dust piles he stood in. The shock had paralyzed Sans in place, freezing him in a fear much worse than his irrational dread for the dark.

_Run._

The word pounded through the skeleton’s skull. Yet the bones of his body ignored the advice. His legs stayed motionless, trapped in the dust as if it was quicksand, swallowing him whole. His mind was still processing his newest revelation.

Some monster- or group of monsters had done _this…_ unspeakable action. And as much as Sans would’ve loved to trick himself into thinking otherwise, there was no way he could lie and tell himself otherwise. Not about something like this. Not at this scale.

The truth left a bitter aftertaste in Sans’ mouth. The kind that made the skeleton wish he had a stomach so he could puke up the vile feeling sitting inside him.

 _Is this really all there is to this twisted place?_ The only consistent thing about this Underground was all the senseless killing. Sans would’ve liked to think that Snowdin and the black and red Papyrus had been a one-off thing. Yet here he was at the edge of Waterfall, nearly halfway across the Underground, sitting in a sea of monster remains.

 _That Papyrus can’t be the only murderer in this place._ No, odds were that the entirety of the Royal Guard were killers. Under the command of _him_ , there could hardly seem to be any alternative. _And after all, someone had to have done this._ Someone in Waterfall, close enough to trap their victims in the same place- their countless number of victims.

There had to be a monster who was a brutal and ruthless killer, eviler than any monster Sans was used to in his Underground. Even eviler than the Papyrus that had tried to kill him for that sake, because this monster wasn't just some killer that tried to dust an innocent monster. No, this monster was a killer that tried and _succeeded_ in that goal.

 _Take care of yourself, okay? It’s dangerous out here._ The skeleton could almost imagine laughter echoing through the hollow cavern, mocking him for his foolishness. He had been right to be paranoid at first. It was so stupid that he’d think he was home free when he’d yet to reach any danger.

_Run._

Once again, the seemingly obvious instruction echoed through his skull. But Sans’ legs refused to move. It was as if they’d been rooted to the spot. All he could do was breathe and fight the overwhelming sense of panic; a panic that seemed to take root much deeper than the skeleton’s legs ever could.

Besides the chaotic pattern of his hyperventilating and the quiet sound of water flowing in the river nearby, there was silence. Complete and utter…

 _Silence_.

…And in that silence, it was very easy to hear the footsteps of the second monster.

 _Just outside the cave._ The sound of dirt shifting under another’s weight alerted the skeleton of their presence. _A dozen or so feet behind me, right beside the entrance._

The skeleton wasn’t alone.  A killer lurked in the shadows among him; for once, Sans had good reason to fear the dark.

The second crunch of coarse dirt he could pick up on seemed a good distance ahead of the last. The newcomer was heading towards him, closing in. Whoever was trailing him was deadly silent, trained expertly to stalk their victims like prey. The skeleton supposed that made sense; it wasn’t like he’d been the first monster to be lured into this graveyard.

It wouldn’t be long until they attacked and Sans became just another number on their kill count. He’d surely be no trouble for a monster who’d created something like this; with his one HP, he couldn’t possibly be any more vulnerable.

 _Do something!_ The skeleton's mind was screaming to his body, the fires of panic burning in the soul in his rib cage. _Do anything- but don't just stand there to die!_

 _Run._ The word repeated in his head once again, as if there was an echo flower sharing its message inside Sans’ skull. Yet this time, the skeleton’s whole body was eager to agree with the one-syllable plan.

Running was something the skeleton was good at. He couldn't teleport like Papy. He had no choice but to put all his faith into fleeing on his own two legs. It had worked with the other Papyrus, so why not treat this threat as the same?

Finally, the message seemed to reach his paralyzed lower body, forcing his legs to jolt forward. Going from a standstill to a full out sprint meant his first few strides were an awkward stumble, where he barely managed to keep his balance as he bolted forward through the cavern corridor, kicking up the dust behind him as he went.

“HEY!” The voice that came from the cave’s entrance didn’t seem welcoming. Though for once, the skeleton couldn’t care less; he had no intention of getting anywhere near the killer.

As his stumble shifted into a panicked run, Sans could hear the other monster moving as well. The murderer hadn’t abandoned their kill at the slightest sign of resistance, sadly; instead they’d given chase after the skeleton. So for the second time that same day, the bony monster was once again on the run for his life.

“Wait!” The second monster’s call sounded feet behind Sans. His pursuer had wasted no time closing the gap between them. Which was worrying, because the skeleton had only just managed to reach of full sprint, and his lead already seemed lost. “Wait!”

Logically, he did no such thing. In fact, the calling only fueled the skeleton to run faster, adrenaline pumping through the veins of his soul. As he rounded the corner at the edge of the cavern, his feet dug into the dirt at the turn, his body doing its best to maintain his speed despite the sharp turn.

The faint red glow of Hotland encompassed him, but the skeleton was in too much of a hurry to celebrate the achievement that he had technically made it to the lava ridden cliffsides. Even the “Welcome to Hotland!” sign had gone dark, as if sensing the state Sans was in.

Behind him, he could hear an attack landing against solid rock, narrowly missing his body as he passed the corner. It sounded like a gunshot. Or a cracking whip.

At top speed, Sans began to leg it across the cliff that sat before the unlit sign. Now, it was probably bright enough to gaze back and see his attacker, yet, curious as he may be, the skeleton resisted the urge to do so. He didn't want to do anything that might slow him down, nor did he want to see the monster who had already murdered many. All Sans wanted was to be safe, back at home. Was that too much to ask?

A jolt of panic seized the skeleton as something unexpectedly grabbed at his leg, attempting to pull him back. Desperately, Sans yanked the limb forward, freeing it from the other’s grasp. He was close now; the lab was visible in the distance, and the bright shades of red that enveloped Hotland’s cliffsides were rapidly approaching.

 _All I have to do is make it there._ Each step brought him closer to the lab. He’d be safe there, certainly. No murderer would dare follow Sans into the lab of the Royal Scientist, right? And yet… the skeleton was still so far away, and he could feel the other monster reaching out to grab him once more, now tightening around his arm. Sans struggled wildly to pull his arm free, but his bright blue glove fell in the motion, the fabric slipping from his hand.

 _Doesn't matter._ The bones of Sans' hand felt exposed without the glove, but feeling exposed was a lot better than being caught and dead. It wasn’t like it was the first item the skeleton had lost today. _Keep running._ he passed an empty sentry station and moved onto the bridge, the monster still right behind him. The skeleton was close now. He could make it. He would make it.

"Stop!" The monster’s footsteps seemed to have stopped at the edge of the bridge. _Why does their voice sound so desperate?_ It sounded as if the other was pleading for Sans to stop- begging even. For a split-second Sans wondered if he should- before hurriedly deciding against it. It was just some cheap ploy that would get Sans killed. If he stopped for even a moment, there was no assurance that the other monster wouldn’t plant a swift attack into his motionless chest. No, better to keep running; he was almost at the lab anyways. Risking it all here would be senseless.

The skeleton made his way to the lab door, only to find another crisis waiting for him: a locked door. As if it was even possible at this point, more panic overcame him. _Why is it locked?_ Undyne never kept the door to her lab shut.  _No no no no…_

Clenched fists of bone pounded fiercely at the door, punching the metal sheet. The sensation of bone smashing against solid material hurt his ungloved hand, but Sans didn't care. He needed to be in the lab. The skeleton glanced back towards the way he came from. The other monster was nowhere to be seen, but that didn't mean he was safe. If anything, it was worse, because the skeleton had no idea where his enemy was.

His knocks against the metal door became more intensive with each second. _Why isn’t she opening the door?_ What if Undyne wasn't home? What could Sans do if he was stuck out here? Those questions only caused Sans to smash his hands harder on the door, unrelenting in his action. The skeleton could feel his unprotected hand start to bruise from the motion. He didn’t stop.

"Please! Open the door!" Sans was stuck on the wrong side of the lab’s heavy metal door. As he screamed from outside, he could only hope that the scientist inside would hear his pleas. "Please!" 

For another moment or two, nothing happened. Sans' hand continued to pound on the door with the same speed and vigor as the soul beating away behind his ribcage. He was just starting to think that Undyne wasn't in the lab at all when the automatic doors flung open without warning, sending the skeleton tumbling in. The unprepared monster fell to the floor inside the lab, and the door was quickly sealed shut behind him, trapping him inside the room and cutting off any source of light.

* * *

_Back to darkness._  

Sans’ soul was already beating too hard for him to properly dread the blackness covering him like a blanket. It was as if his senses had hit an overload. Another layer of fear, another cause for panic, hardly seemed like much in his present situation.

At first, the skeleton couldn’t bring himself to get up. He simply laid where he’d fallen, wheezing on the floor- thanks in part to a shortness of breath, as well as the fear, free-falling in his soul. _Better to let the terror settle before I get up,_ Sans convinced himself, breathing deep.

Bright blue eyes pierced through the unlit room, searching for light where none was to be found. It was even worse in the lab than it had been in Waterfall; there’d at least been some light in the river riddled caverns, but here, the thick color of shadows coated everything. The skeleton could see nothing, which did not help to calm the pounding blue organ in his chest.

 _That was real close._ Sans wanted to say that this time had been even closer than his bout with the other skeleton, yet he couldn’t say for sure; his encounter with the other version of Papyrus felt like it had been lifetimes ago. Though in actuality… it had been little more than an hour or so prior.

It took a few minutes before the panic of being in another near-death experience began to ease. His soul still pounded hard in his chest, threatening to burst out of his rib cage. It seemed unreal to Sans that had been the second time he'd escaped the clutches of a killer in the same morning.

 _I did it… I made it._ As exhausted, worried, confused, terror-stricken, and uncollected the skeleton was feeling, a weird since of pride came with the accomplishment of getting to Undyne’s lab. _I was ambushed by two separate killers and made it out unscathed._ Not only had he escaped them, but he'd also made his way to Undyne's lab, in a manner of only a few hours.

 _This really could have been a lot worse._ The only evidence of Sans' experiences was the loss of both his glove and bandanna, the small scrapes covering his bones, and the tattered rags he’d once called clothing. Yet materialistic things and minor cuts aside, the skeleton was fine.

 _I guess Alphys' training has really paid off._ The Magnificent Sans was getting to be just as strong and brave as the Captain of the Royal Guard herself. If she could only see him now- she'd haveno choice but to let him join the Royal Guard!

Speaking of which, Sans couldn't wait to tell Papy about this whole thing. His big bro would be so proud of how well he'd handled himself. The skeleton could already picture it in his head- Papyrus would scoop him up as soon as Sans got back and plant a small kiss on his forehead, like he always did when he was worried about the younger monster. Even though he always told his big bro he was too old for kisses, Pap had never listened- and he really didn't even expect him to. Secretly, the smaller monster relished the attention. After the taller skeleton finished making a big fuss over Sans, he’d finally get his chance to tell him all about his brave exploits and how he’d gotten back to their Underground... with the help of Undyne, of course.

 _Right._ The thought of the Royal Scientist reminded Sans that he wasn't home yet- and that he was still lying face down on the tile floor. The small skeleton was quick to fix that, pushing himself up from the cold tile. The skeleton winced slightly at the pain that came as he put pressure on the newly bruised bones of his right hand.

 _Ow._ Even though he couldn't see it for himself, Sans knew it was bruised pretty bad. The skeleton always wore his gloves to keep his small, fragile hands protected. The weaker bones of his hands weren't as strong as his other ones.  _No worry._ Sans gently massaged the damaged bone with his other hand.  _Nothing a little first aid won't help._ The skeleton always kept an emergency kit at the house. Once he got back there, he could patch up the rough bruise. Though before that could happen, Sans needed to find Undyne.

 _Okay._ Once more, Sans looked back up into the darkness; his soul dropped in his chest at the sight of black nothingness that finally met him head on. The skeleton could feel the terror in his chest welling up once again, strangling him as the fear for the dark took over.

 _Stay calm,_ he told himself. His fists tightened, and fingertips curled into his bony palms. His ungloved, bruised hand protested the action, but nonetheless remained obedient. _This really isn’t too bad,_ Sans tried to convince himself; after all, there was nothing here he needed to be afraid of. Unlike Waterfall, where a silent killer had lurked in the shadows, nothing of the sort would be found in the lab of the Royal Scientist. _Just take it easy._ The skeleton closed his eyes tight and tried his best to keep his breathing steady.  _Nothing but a little darkness._

With closed eyes, calming himself became a much more manageable task. When all he could see was an artificial darkness, formed by an absence of the two magical sensors normally present in his eye sockets, the actual blackness surrounding him hardly seemed real. By abandoning his sense of sight, Sans could almost convince himself that he wasn’t be smothered by a thick black blanket of shadows; hiding behind closed eyes almost made reality disappear entirely.

It took a moment to ease his pounding soul back down to a healthy pace. The skeleton decided it’d be best to traverse through the dark laboratory without his sight, ignoring the blackness as well as he could. It wasn't like it mattered much, either. The darkness was just as debilitating either way.

With bony hands outstretched before him, ensuring Sans didn't run into anything, the skeleton took his first steps through the room. Quickly probing the walls by the door found him no light switch. _Maybe they use light sensors or something._ Sans had no clue, but it seemed as good a guess as any. _Why’s it so dark in here in the first place?_ Wasn't Undyne here? The skeleton doubted the monster worked in the dark.

After what felt like an eternity of stumbling blindly through the room, searching for a switch that did not exist, the sound of someone clearing their throat gave Sans pause. Cautiously, the skeleton peeked an eye open- only to be greeted by perfectly well-lit surroundings.

 _Oh._ All the lights were on. _When had that happened?_ His other eye blinked into existence and Sans was left wondering how long he'd been dumbly moving through the bright lab room with his arms extended and eyes shut tight. 

"Can I help you?" The question echoed from the second floor of the lab, the Royal Scientist’s sleeping quarters. The skeleton immediately recognized the voice, but to his surprise, its owner was not someone he had been expecting.

Swinging his head to the edge of the platform looming above him, the second monster came into view. She was clothed in a white lab coat, typical attire of the Royal Scientist. Yet that wasn’t right, because the monster Sans’ eyes met with wasn't the Royal Scientist. Or at least, not the one the skeleton was familiar with. _What’s she doing here?_

Beneath the lab coat, she wore a black and red striped shirt. Her glasses were tinted a dark red, and her black pants clung tight to scaly thighs. The red gloves she wore looked just like the ones that Sans had felt latching around his neck only an hour ago. Seeing the monster is this clothing, rather than in her heavy armor or a loose tank top with jeans, was unusual. But in a weird way, it seemed to fit just right.

"Hey Alphys!" Sans greeted the other monster eagerly. It was confusing to see the warrior here. The Captain of the Royal Guard was dressed in a manner that fell more in line with Undyne’s style, save for the dark red color palette. Yet the friendly, familiar face was such a comfort that the surprise hardly fazed the skeleton.

"I... don't believe I know you." The scaly yellow monster scrutinized every aspect of the newcomer with a pair of suspicious eyes that seemed to ask the obvious question her statement implied: “ _who are you?”_

“I’m looking for the Royal Scientist,” the skeleton cheerfully responded, missing the other monster’s underlying question. “Is she here?”

“You’re looking at her.” The scaly yellow monster deadpanned.

 _Oh._ Sans supposed he should’ve guessed as much from the lab coat. It wasn’t like there could be any other explanation for her appearance here- unless she was playing dress-up, which seemed highly unlikely to the skeleton.

 _So, this Alphys is the Royal Scientist- here, at least. How does that work?_ The version of her Sans knew was much more enthusiastic about breaking things rather than building them. Such a trait would hardly be productive for a monster spearheading the development of monster-kind.

The scientist standing on the loft overhead cleared her throat once more, calling Sans’ attention back to her. “Who are you?”

 _Oh yeah- right._ Introductions- luckily, Sans was the best at those! Papy always said first impressions meant a lot. So of course, that meant he needed the _best_ first impression out there; the skeleton had even given himself a super cool nickname, just to impress others. His spine straightened as he stood tall, trying to make himself look as important as he could. "I am the Magnificent Sans!"

Unfortunately, the scientist didn't seem terribly impressed. His spirits sinking to the floor, the skeleton weakly attempted to recover. "Or… you know… Sans is fine too."

"Doesn't ring any bells," The scientist remained unmoving from where she stood, looking down on the other monster. "Is it supposed to?"

"No," Sans admitted, awkwardly rubbing the back of his neck. He still needed to remember that this Alphys wasn't the one back home. The skeleton didn't know this version of his warrior friend, and she didn’t know him.

"So why the hell is it that you’re here?" Instinctively, the strong language made Sans flinch. He’d noticed that the other Papyrus had sworn a lot too. _Guess that’s just something a bit more common here._ In his Underground, the skeleton never heard anyone openly swear out loud, besides maybe one or two slip ups. But that didn't matter- no one was perfect! Even Sans had accidentally said  _h-e-double hockey stick_ that morning when he had encountered the other monster. Here though, in this Underground, it seemed monsters were a lot more open about the whole thing. Like it was accepted as normal, which was a worrying thought.

"I need your help," The skeleton said, twiddling his bony thumbs in his hands. He always got a little flustered when the vulgar language was used around him.

"Why would I help you?" The scientist arched an eyebrow at the other monster, as if he’d just said something ludicrous.

"Because- because you're the Royal Scientist!" Sans replied, but he knew that wasn't much of an answer.

"So? Just because of some stupid title doesn't mean I have to fix your problems," The scientist shook her head, obviously annoyed. "I’ve got better things to do. Get lost."

Sans didn't plan on doing any such thing. The skeleton knew couldn't go back outside to Hotland, where the killer could be lurking. He needed to convince this version of Alphys to help him- no matter what. That was the only way he could even hope to go home, to his Underground, and to Papy.

 _How would I convince Alphys to help me?_ Not this version of her, the mean, vulgar scientist, but _his_ Alphys, the fun, friendly Captain of the Royal Guard that taught him how to cook tacos and defend himself- sometimes even at the same time! The version of the monster who had a major crush on her best friend, Undyne, the Royal Scientist Sans knew back home. The monster who fought with a metal axe in hand and protected all the Underground from humans- that Alphys. How would the skeleton convince her to help him?

 _I wouldn't have to._ Sans knew that if he just asked the mighty warrior to do something for him, she'd do it. Because he and Alphys were friends- the best of friends. The Captain would help him without so much as a reason to do so; she was just that great, and their friendship meant that much to her.

Sure, Sans wasn't friends with this version of her, but he knew they had to be alike in some qualities. Alphys was still Alphys, even if she used harsher language than the small skeleton was comfortable with and wore a lab coat with black and red garments. Surely this scientist valued friendship, the great bond between any two monsters, just like her warrior counterpart.

"Did you not hear me? Get out!" The scientist pointed to the left, back to the door Sans had come through. She wanted him gone, yet the skeleton was determined to convince her otherwise.

"Please," Sans’ voice was a lot weaker than he would have preferred. A small part of him must’ve realized how desperate his situation was. Failing to enlist Alphys’ aid didn’t just mean he was stuck in this version of the Underground, it meant he’d be back out in Hotland; he’d be a goner.

The killer may or may not have been waiting outside, but that remained only one of the skeleton’s worries. If the Royal Scientist turned him away, the monster would have nowhere to turn after the lab. He would die- either from starvation, or some other killer would swoop him up for a few easy EXP. That meant this conversation was make or break; Sans had to convince the scientist. There was no way around it. "I need your help."

"Give me a reason I should care," The lack of emotion in the monster's response made it clear that at the current moment, she didn't.

"Because I'm your friend."

Behind red tinted lenses, the Royal Scientist’s eyes narrowed at the word, almost as if it was unfamiliar to her. "I don't even know you." That was true. She’d only just learned his name minutes ago. Before then, this Alphys likely hadn’t even known he’d existed. Sans' argument must've sounded like crazy talk to her.

"Well I'm not  _your_ friend. I'm friends with… _another_ you," The explanation felt odd and unconvincing, even as the words tumbled from the skeleton's mouth. Sans knew he probably wasn’t making any sense to the other monster, who had no way of understanding what he was talking about. But… he had to say something quick to make sure the other monster didn't throw him out. Even if it really _did_ sound like crazy talk.

"Another me?" There was confusion evident in the other monster's voice. The skeleton’s explanation had thrown her off and distracted her from her pressing desire to throw him back out into Hotland. "What are you talking about?"

"I'm- I'm not from here," If the statement had shocked the scientist, she showed no sign of it. Sans had figured he probably already looked a bit out of place in this Underground. Save for the riverman, all this Underground’s monsters seemed to have an unexplainable fascination with the colors red and black. And… they were all so rude- and vulgar, too. Heck, of the monsters Sans had encountered, two of four had been murderers. With his weak attacks and distaste for foul language, the skeleton stuck out like a sore thumb. Especially while sporting bright blue colors that glowed against the dark hues. 

"I came from... another Underground." The idea must’ve sounded nonsensical to any monster besides himself. He only knew it to be true because he’d personally experienced the vast web of differences between the two; to a monster who hadn’t a clue what Sans had been through, the skeleton may as well of been a raving lunatic.

“Explain.” Instead of calling him insane, or one of the other hundred names he’d been preparing for, the scientist kept Sans talking.

Rather than kick him out, Alphys gave him an opportunity to share his story. Which meant at the very least, she was interested in what he had to say. By no means was that a promise to help him home, but it was a start, and the skeleton sighed internally, letting a wave of relief roll over him. A start was all he needed to convince the Royal Scientist, he was sure.

“This morning I woke up… well, _here_.” Sans rubbed his shoulder anxiously, suddenly very conscious of his word choice. “In a version of the Underground that’s nothing like my own.”

“In Snowdin, a monster attacked me. He was a skeleton who-” _Who looked just like Papy._ The words caught in Sans’ throat. “-who seemed intent on dusting me.” That part of the story wasn’t important, he decided.

“I didn’t have a clue what was going on. I just knew that everything here was all so… _wrong._ I figured that if anybody could understand what had happened, it was you… If anyone could help me get home, you could.”

“From Snowdin, I crossed Waterfall to get here.” Behind red lenses, the scientist’s eyes shot open wide, the first sign of emotion she’d given since Sans had started his story.

“You made it here through Waterfall?” The shock was evident in Alphys’ voice.

“Well… yeah.” The skeleton was worried he’d said something he wasn’t supposed to. “I didn’t have enough for the boat ride from Snowdin directly to Hotland- only enough to make it to Waterfall. On my way from there to here, another monster attacked me…” Sans smiled weakly, remembering the cause for his bruised hand. “Which may have had something to do with me pounding on your lab door…”

The Royal Scientist made no response. Thanks to the tinted glasses she wore, the skeleton had little idea what the other monster was thinking or feeling. Nervously, Sans chuckled. “Heh… sorry about that, by the way.”

If Alphys heard his apology, she didn’t show any sign of it. When she opened her mouth to talk, the emotion she was feeling became obvious to the skeleton: confusion. “It’s just that monsters who go into Waterfall don’t tend to make a reappearance all that often.” The cave floor, covered in dust, immediately came to the forefront of Sans’ thoughts. “I’m trying to figure out how exactly you did.”

 _Oh._ Even though he’d already escaped from Waterfall, dread filled the skeleton. He really had underestimated the River Person’s warning. It seemed that the caverns had a reputation of danger throughout the whole Underground. Every monster must’ve known that, except for Sans, who was completely unfamiliar to this place. _Guess I was luckier than I realized._

“It doesn’t really matter.” Alphys seemed to drop the subject, though she kept eying the skeleton warily. She seemed capable of seeing even the tiniest details of the skeleton: every scrape, every bruise, and cut. The scientist was dissecting Sans with her eyes as if he was a foreign specimen, which, technically, he was. “What was it you wanted from me again?”

"I- I need your help… so I can get home." The skeleton request went largely ignored by the other monster. The Royal Scientist responded only with a grunt of acknowledgement, which didn’t exactly reassure Sans. Alphys’ eyes continued to gloss over him, evaluating him as she was the doctor at an annual physical. Which was fitting, seeing as how she already had the white coat on.

Eyes never leaving him, the scientist finally moved from her spot on the upper platform. Without uttering a word, she descended to the first floor of the lab in silence, riding the escalator down. Alphys’ attention remained fixated on the smaller monster as her scaly feet clicked loudly against the tile floor with each step. Each footfall echoed through the large laboratory.

“Will- will you help me?” Still no answer. The Royal Scientist kept walking towards him, her pace not slowing until she was practically on top of him, her face hovering directly before his, the two monsters hardly a step from each other.

Behind red glass, beady black pupils were trained on Sans. Alphys continued to look at him as if he was some sort of abnormality. Her silent observation had gone on for too long, yet the skeleton was hardly in a place to make demands. Both monsters knew just how desperate he was; Sans’ life lay in Alphys’ hands. Even when the skeleton pressed her for a promise of help, the scientist felt no rush in doing as she pleased, inspecting every part of him for reasons which remained unknown to Sans.

"You are in... very good condition." It was such a strange thing to say, yet the scientist seemed stunned by the revelation. Without warning, a gloved hand launched forward and took hold of Sans’ chin. The skeleton flinched back, instinctively attempting to break out of the other’s hold, yet this Alphys’ grasp on him was stronger than he would’ve expected. The Royal Scientist tilted his skull to both sides, examining each side from up close. "No cracks. No scars," she remarked, as if taking notes.

"Um…" Sans wasn't sure how to respond to the situation. Alphys’ evaluation of him seemed to have little to do with helping him get back home. The scientist's hand dropped back to her side. "...thanks?"

 _I’m not sure I would say that I’m in “very good” condition_. Of course Sans didn't have any cracks or scars, but he'd never known a skeleton who did. Granted, the only skeletons he had ever known were himself and Papy. _And the other version of him I met today._ That version of his brother did have a scar; Sans had almost forgotten. Right across his eye, a real nasty one, too.

Putting that exception aside, scars and cracks were rare for skeletons. So while he may not have had any damage of that sort, he certainly wasn't in _great_ condition. He was doing better than he’d expected after multiple run-ins with murderers, but better than expected and “very good” were two different conditions.

Looking down at his body, he saw- or rather, didn’t see- his two missing accessories. The clothing he still wore had become shredded rags. His exposed white bones were scratched and cut all over. His ungloved hand was bruised a dark blue. And while the pain was hardly excruciating, Sans had certainly been in better states before- states that _did_ qualify as very good. This wasn’t one of them.

Smartly, the skeleton to keep that to himself. He decided it was better not to upset the monster he was asking for help by disagreeing with them. “…well?” Sans nervously reminded the scientist he had asked her a question.

The Royal Scientist hummed idly, as if she was thinking it over in her head while she continued her inspection of Sans. Alphys reached out for the skeleton arm, grabbing it and placing the bones in both of her red gloves. This time, Sans didn't flinch like before.

He may not have known  _what_ it was she was doing, but the scientist seemed focused on finishing her task before she gave the answer to his request. It wasn't the skeleton's place to question her actions. He had come to her asking for help; it would be rude of him not to play along with whatever... this was.

Sans jolted a bit as the scientist suddenly turned the arm over, the motion a little too harsh. Dropping the limb, she proceeded to do the same with his other arm. "No signs of cracking here, either..." The scientist no longer sounded confused. Her investigation of the skeleton seemed to have helped her reach some sort of conclusion.

"Yeah- I've... never even broken a bone before." Sans had come close, but he'd never been injured bad enough to cause permanent damage like that before. The closest he’d ever gotten had been when the skeleton had smashed his ribs up during one of his earliest training sessions with Alphys- the Captain of the Royal Guard Alphys, obviously.

"Really?" The scientist only sounded a bit surprised. "Not once?"

"Nope."

"Isn't that interesting…" The scientist finally stepped back, giving Sans a chance to relax, the examination seemingly over and his personal space reclaimed. "Your Underground must be pretty easy."

Sans’ soul jumped at the mention of his Underground. "You believe me?" The skeleton had been afraid the scientist would discard his story as that of a madman’s. _He_ still thought it was crazy.

"Of course." The scientist smiled, but not in a way that came off as comforting or sincere. The expression felt forced and fake, like it was straining the rest of the scientist's face. _An A for effort, at least,_ Sans thought. _I guess some monsters just have a more natural smile than others._ "The theory of alternative timelines has been something I've thrown around in my head a bit, but… well- I guess it's no longer a theory anymore."

 _"Timelines?"_ Sans repeated back. Oddly enough, the word sounded… so familiar to the small skeleton. And yet, he could swear he’d never heard it before in his life. "What are those?"

"In simple terms, imagine a whole bunch of versions of this world, with differences ranging from major to minor, spread across all existence," the scientist explained, strolling across her lab to a table as she did so. "Imagine thousands to infinite different universes and alternatives realities of your own, all filled with different versions of the people you know."

It sounded complicated, even in the scientist's "simple terms." The idea made the small skeleton's head spin. Sure, Sans had already known that this wasn't his Underground, but still- infinite other universes? An endless number of Undergrounds, all filled with an unlimited number of monsters, all different in some way or another. Just the thought that so much existed, so many worlds, equally validated in their existence, at the same scale as him own…

It made Sans feel very, very small. 

The skeleton would be a bit more comfortable with two or three- maybe four or five. But... infinite? So many versions of his reality that they could be measured only with a word the described the innumerable. Countless variations. Endless alternatives versions of everyone Sans had ever known…

"Your presence here proves all that to be not just a theory, but reality." The scientist paused for a moment, stopping behind her desk to look back at Sans. "Isn't that utterly fascinating? I mean, the implications are just… astounding.”

 _Yeah, that’s one way to look at it._ The skeleton groaned quietly, pressing his pounding skull into his hands. He could wrap his head around very little of it, save for the fact that it was surely going to give him a migraine.

"It's a bit much, huh?" The scientist seemed amused by his reaction. As Sans rubbed his temple, trying to stave off the impending headache, Alphys shuffled through the messy papers on her desk, assumedly looking for something amongst the clutter. "Don't worry. It won't bug you too long."

"Huh?" Sans hadn’t been listening. “What was that?"

"Oh, it’s just that- well… nothing." Alphys’ response was forgotten as the search of her desk came to a halt, the scientist finding exactly what she’d been looking for. Her red glove came to rest right on top of the item, settling on its wooden shaft. "You ready?"

Sans soul pounded in excitement.  _Did she mean-?_ "Are you going to help me get back home?"

The scientist looked back up at the skeleton. "I'm going to try. But don't take that as a guarantee.”

The smaller skeleton could hardly contain his joy. It wasn't a sure thing, but it sure as heck beat going back out into the rest of the Underground. "Thanks so much Alph! Thank-you thank-you thank-you!"

The scientist flinched at the use of the shortened name. She didn’t seem too pleased by the excessive thanks, either. "Don't call me that."

"Oh." Sans hadn’t thought this Alphys would dislike the nickname he used for her back home. “Sorry.”

"Yeah, whatever. Just don’t do it again." The Royal Scientist gripped her hand around the item it had been resting over. The metal hammer emerged from the stacks of paper and fell naturally to the scientist’s side. "Just follow me."

Crossing the lab’s first floor, Alphys led Sans to what he’d always assumed to be a bathroom door- in Undyne’s lab, at least. Yet here, there was no mistaking that to be the case; after all, Sans had never seen a bathroom with a passcode lock.

The scientist inputted the code into the number pad with her free hand, the hand with the metal tool hanging idly by her side. The door quickly shot open, and the Royal Scientist motioned Sans to move forward. "After you." The skeleton hurried into the small room, completely uncertain of what he should expect as his energetic feet carried him through the doorway.

"Huh?" It was empty. And while the square room certainly wasn't a bathroom, there was little to tell the skeleton what it could’ve been. Quickly scanning the room, the only thing the skeleton could see was a control panel installed on the back wall and-

 _And nothing._ Because as soon the skeleton made that observation, there was a sickening crunch of metal against bone. The pitch-black darkness from before returned, only this time, it wasn't because the lab’s lights had gone out.

The skeleton's limp body tumbled to the elevator floor, sending Sans sprawling to the ground, unconscious. Behind him the smiling sociopath who called herself a scientist stood in the doorway, the hammer still extended in the downward swing that had earned her a new test subject.

**Notes for the Chapter:**

> ~Edited 7/16/17~  
> Boy, this one was a pain to rewrite. For those curious, the first half of this chapter was scrapped and then rewritten, as I wanted to change almost of its events. I went through 3~4 different variations of the Waterfall segment until finally settling on this one. Still not even 100% sold on it myself, to be honest.  
> The second half of the chapter was MUCH easier. I only polished up the dialogue and expanded Alphys' and Sans' conversation a bit.  
> Hopefully, the next chapter won't take so long to edit, but no promises.


	8. Chapter 8

**Summary for the Chapter:**

> Underswap Papyrus and Undyne get to work, and Underfell Sans tries to find the best way to occupy his time. Underswap Sans deals with his warm welcome to the Underfell lab.

**Notes for the Chapter:**

> Back and forth between Underswap and Underfell this chapter- will be the same for the next chapter as well!
> 
> So this chapter seems a lot more different than the previous ones, at least to me anyway. The events of this chapter happen a bit faster, so fair warning.
> 
> Enjoy!

Feeling useless was something the smaller skeleton was well acquainted with. Back in his universe, he was used as nothing more as a fuck toy or a punching bag- depending on the day. It was the only things he was any good at. Sans' was shit at his job being a sentry. Everyone in the Underground's Royal Guard knew that. The skeleton constantly fell asleep at his post. The chances of him stopping any intruders- human or monster- were next to nonexistent. He was so weak he would've died years ago- should've died years ago- if it hadn't been for his brother "protecting" him.

Seeing how his only use was being used by other, stronger monsters, it wasn't too surprising to the skeleton that he served no purpose in this lab either. 

For a start, he couldn't even figure out  _what_  it was that the other two monsters were doing. Yeah, the Royal Scientist had told Sans that they were building some sort of machine to send the skeleton back to his universe and get their Sans back where he belonged. But to him, it seemed like all this Papyrus and Undyne were doing was just running around like madmen connecting power lines from the Core to random parts of the metal block they were building.

"Just put it here-"

"If we put it there, it'll burn out the controls!"

In fact, Sans wasn't even fully convinced that the two of them weren't doing that. The construction of this new machine had been chaotic and unorganized. The skeleton didn't see how this thing was supposed to even work. It looked like a giant piece of junk. Actually, that was what it was. A bunch of pieces of junk thrown together. The scientist and the larger skeleton had run out of scrap metal to work with after they'd just finished building the base, so this Underground's version of Papyrus had teleported away to the nearby junkyard to pick up more metal scraps.

If this was what hours of work in a dark lab on the parts of two monsters amounted to, then Sans wasn't very impressed. The machine they had produced was nothing more than solid metal trash. There was a small glass container in the center of the metal machine, small enough that Sans' own skull couldn't even fit in there. Wires dangled precariously along the outsides of the machine, attaching to circuit boards on the inside of the machine that seemed to serve no obvious purpose to the skeleton. The small, touch screen monitor that had been attached so it could act as some sort of control panel for the whole contraption was the only thing that Sans could even remotely understand.

This... _thing-_ because Sans refused to pretend it was a machine for any longer- hardly seemed capable of sending the skeleton back to his universe. It seemed even less likely to pull back his double into his own timeline. But hey, what did Sans know? He wasn't a scientist. If this Royal Scientist thought it was going to work, then he might as well as give it a shot, right?

"Hey, uh...  _you,_ " Undyne awkwardly addressed the other skeleton, not quite comfortable calling him Sans. It was just that this monster was so unlike the small skeleton friend of hers that it was hard to imagine them sharing even the same name. "Could you... give me a hand?"

"Uh... yeah," Sans replied, unsure. He pushed himself up from his spot against the wall where he'd been sitting for the last few hours. This had actually been the only time the other monster had asked for his help.

"It's nothing big, I just need some help with this part," Undyne indicated to a sheet of metal that was only loosely attached to the rest of the machine. "Can you just... hold it in place?" The scientist glanced back to the other skeleton in the room, who was hunched over a table working on something that Sans couldn't quite see. "Papyrus is a bit busy."

"Got it," The smaller skeleton made his way to the scientist, who handed him the part. It was a bit heavier than Sans would've expected someone like this dorky scientist to be able to handle.

"Yeah- just hold it right there," She said, turning around to grab a set of tools. The Royal Scientist came back with a blowtorch, which Sans assumed she was going to use to wield the metal pieces together. "You... uh, might want to look away." 

The skeleton did exactly what the other monster had instructed, turning away from the torch. Sans could feel the heat of torch igniting, burning into the metal sheets. Across the room was where Sans' wandering gaze settled, on where the other version of his Boss was working. This Underground's Papyrus was moving with a remarkable speed. Whatever task he was preforming, he made sure it was done efficiently and as quickly as possible. His own panic and worry kept fueling him to go faster. Sans wasn't even sure he'd seen him take a single moment of rest since they'd gotten here.

"He's not usually like this," Undyne said quietly over the sounds of the tool she was using, as if she was reading the other skeleton's thoughts.

"Yeah?" Sans kept his eyes trained on the other monster, who seemed to be building a smaller machine at his own worktable. "So what is he usually like?"

"Well..." It took a moment for the scientist to think of the answer to the question. Sans could feel the fire of the torch moving closer to his arms, the heat beginning to get to his bones beneath the black sleeves of his jacket. It hurt a bit, but nothing the skeleton couldn't handle. Not like he hadn't experienced things a hundred times worse a thousand times over again. "He's usually a lot more relaxed than this," Undyne finally responded.

"Oh?" Sans had seen that a bit this morning- but he had figured that it had only been some sort of cover up for the worry and fear the skeleton had actually been experiencing.

"Yeah," Undyne moved the blowtorch away from the skeleton holding the part, moving to another edge of the sheet that needed to be put into place. "He only ever gets worried about really serious issues."

"Like his Sans going missing," Sans had more than picked up the fact that this version of his little brother seemed to care for their other sibling.

"Yeah. Anything involving Sans usually sets him off," The scientist continued while the monster they were talking about remained oblivious to the topic of their conversation. The other Papyrus was off in his own little world, focused intently on building whatever it was he was creating. "But, to be truthful- I've never seen him this bad before."

Sans adjusted his grip on the metal. "Never?"

"Nope."

The smaller skeleton could sort of get it. When his Boss had been little and Sans was the one taking care of him- not the other way around- almost every waking moment of every single day had been to making sure his little brother had been alright. Sans had sacrificed the comforts of his own life just to make sure his little brother safe. It was the same exact way here, only that the roles were reversed.

This Papyrus cared for his Sans more than anything else in the world. His little brother was his life, just as Boss had been Sans' own when he had been little. Heck- Boss still was his life. Just in a few other ways. Maybe they weren't so different.

"And... there," Undyne let the blowtorch go out, backing away from the newly attached metal scraps. "All done," Sans let go of the part he had been holding in place, pulling away from the rest of the machine. Apparently he had caught his sleeve between the two parts when he had been holding them together, as a small piece of his fabric got caught between the two sheets, ripping from his jacket.

Sans was too lost in thought to care. His jacket was just one of many. They were all torn and ripped up. One more scrap of fabric lost from just one of them wasn't the end of the world.

"Uh... thanks," The awkward scientist said and Sans nodded in response, not really paying any attention. His eyes were still locked on the other Papyrus, his mind trapped in thought. 

 _A version of his brother who actually cared about someone other than himself._  Sans had trouble getting his head around the idea. After years of torture and cruelty at the hands of his own little brother, it was impossible to see him as anything other than Boss. The mean, abusive, Captain of the Royal Guard. One of the strongest monsters of the Underground.

But here it was. Another version of the skeleton. One that was typically "laid back and relaxed." One that knew all about science and machines. One who didn't abuse his own version of Sans. One who didn't look at their brother as a toy- as something to just use and throw aside for later.

_How strange._

* * *

Every passing moment hurt. Every beat of his soul, every single second he spent awake, and every breath Sans took. It all hurt. Every gasp of air the skeleton struggled for came with the same intense wave of pain, flooding over the whole of Sans body. The skeleton's pained breathes were no more than wheezes; quick, sharp, and irregular, Sans finding it impossible to calm himself.

 _This was bad._ Real bad. Sans' head was pounding so fiercely that the skeleton could barely think straight. The sensation of pain was so unbearable that it was overtaking the whole of him, but it was very obviously coming from his skull- no surprise there. He hadn't forgotten what had happened to him. How could he have?

He was bound at his wrists and ankles by metal cuffs that kept him pinned to a table. And it was so dark that even if Sans had been in a sensible state, he would've been unable to see the very room he was trapped in. But Sans' fear of the darkness was the least of the skeleton's worries right now. 

His skull was broken. Completely smashed in. Even without seeing or feeling it, Sans knew it was the truth, because the pain that came with the injury was more than the skeleton could take.

Sans... Sans had thought he had known pain. He thought he was well familiar with the hurt that came with being injured- emotionally or physically.

The skeleton had thought pain had been like the time when he'd fallen from the bridge in Waterfall and smashed up some of his ribs. Or whenever had and Papyrus ended up arguing- the anger and hurt burning in Sans' soul. The small skeleton thought he had known the torments and agonies of suffering whenever he watched, powerless, as his big bro slipped back into one of his depressed states. When whatever he did was absolutely useless to pull the larger skeleton out of his slump.

Yes, that had all been pain- real pain, that Sans had been forced to go through in his Underground. But the thing was that none of that could compare to the  _raw_  pain he was enduring right now.

He couldn't even bring himself to move, because even the slightest of twitches caused his body to flare up to an even worse extent than it already was. All Sans could do was keep his body as perfectly still as possible with his eyes shut tight, hoping for the pain to go away. Begging for it to disappear, even though he knew it wouldn't.

How was it that he even still alive? Something like this should've killed him. He was so fragile with his one HP- a brute force attack like this, even to an area other than his soul, would be an assured way to dust him. But he was still here. Why was he still here?

The scientist- Dr. Alphys- she'd done this to him. She'd bashed the back of his skull in with a metal hammer as Sans had been entering the elevator. Why? What happened to her helping him get back to his Underground- or his universe? She'd said that she would- she had promised. How was a hammer to the back of the head anything close to that promise?

Sans kept wheezing as the blackness around him threatened to suffocate him, and smother his whole body and soul in the darkness.

 _Shit._  He swore mentally to himself- an action that he wasn't used to.  _This was real bad wasn't it?_

Never in his life had the skeleton been in a situation like this... at least, not that he could remember. Abandoned... alone... and trapped. The feelings of loneliness from before had come back in tenfold, yet this time Sans couldn't distract himself from them. There was no bright blue echo flower the skeleton could whisper into and pretend that all his worries were gone. No stupid game he could play to forget what he didn't want to think about or remember.

Nope. Here, in this dark, black room he was confined to, his body chained to a table in the center of it, there was nothing but the darkness. No distractions. Nothing to keep him from his thoughts and feelings.

He'd never been this alone. He'd never been this sad.

Sans could feel the tears slipping from his eyes once more, and the small skeleton wasn't even sure he could bring himself to stop them even if his hands weren't bound. The crying wasn't like the panicked sobbing from before. It wasn't like the silent tears that fell when Sans had thought about his Underground- about his life and his Papyrus. Yes, these tears were silent too, but there were no fond memories of the past that triggered them. These new droplets formed on their own accord- from nothing but pure sadness.

 _"I... I can fix this,"_  The words slipped from Sans' mouth in no more than a whisper, and Sans knew they were a lie as soon as they came out. He couldn't fix this. He couldn't escape this room. This Underground. This universe. This "timeline." He was helpless. His hands were tied- literally- and his battle body was gone. The armor that protected his soul, stripped from him and replaced with a sickly green, oversized shirt. His boots, pants, undershirt, and one remaining glove were all gone too.

Sans was screwed and he knew it. There was no way he could fix a situation like this. There were no stupid lies he could tell himself anymore to keep him comfort. The only possible way he could get out of here was if someone else- anyone else- saved him.

But nobody was going to. His Papy wasn't part of this Underground. The Papyrus here was a cold blooded killer that wanted to kill Sans, the opposite of saving him. His other friends, Undyne and Alphys, were very much the same- stuck in an alternative reality where they were powerless to help the smaller skeleton. Nobody was coming to help Sans. Nobody could possible save him from whatever laid in store for him.

 _It could always be worse._  The motto the skeleton had adopted from the River Person repeated in his head, taunting him. Sans managed a choked laugh at the thought, and the reaction sent shock waves of pain down his spine and through his bones but Sans couldn't stop himself. It was a joke. He could hardly see how anything could get worse than  _this._

Sans was stuck in a dark room, all by himself- with no hope of anyone else coming to save him. The scientist he had thought was going to help him had nearly killed him with a hammer to the head. He was stripped of his armor, and his hands were bound tight. The pain in his chest was the only thing drowning out the feeling of the darkness caving in on him. Sans didn't know even how he was alive- nor how long he would continue to be allowed to live.

 _How could anything be worse than this?!_ Sans wanted to scream the question out- to demand an answer from the darkness that seemed to be his only company in this desolate place.

That answer came to Sans as the sound of scaly feet scraping against tile flooring and the rolling of a cart came from down the hall next to his room.

* * *

More time passed- probably another few hours- and neither Undyne nor the larger skeleton had asked much of Sans' help. In fact, it seemed like the other Papyrus had barely even noticed Sans' presence. The two hadn't even shared a word the entire time they'd been together in the lab. Undyne didn't pay much heed to him either. The Royal Scientist was too focused on building the machine to say much.

All of which was perfectly fine for Sans. Being ignored was better than being abused- that was something he'd learned a long time ago in his timeline. Attention wasn't something you wanted, so if a monster wasn't paying any mind to him, it was better to just make himself seem small and not press his luck.

Sans had sunk back into his corner, pressed against the two walls next to the entrance of the room. He was fine with being ignored, expect for just one thing. It left him alone. Not in that emotional, touchy-feely kind of away- alone with his thoughts. With his mind. Which, if you'd been though half the messed up shit Sans' had been faced to endure through the years, was not something you wanted.

Though, he had his own little ways of distracting himself from those thoughts. And while Sans' methods for doing so weren't always...  _the best,_  it sure as hell beat revisiting an organized list of all his failures and regrets.

Sans called it chipping.

It'd started after a particular violent night with his brother. Not the good kind of violent either-  not the one where he at least got off at the end of it. The kind where he was brought to the edge of his life- only to hang there, wondering if that night was the one when his Boss finally finished him off. If the Boss was finally done with dealing with the smaller skeleton and had decided that his brother was better off dead. 

Sans had been tossed aside on the floor of his room, among the garbage and filth that he was used to. He had been too weak to pull himself across the floor to his mattress. Yet the pain he'd been in had proved too much for the skeleton to fall asleep either, so he had no choice but to wallow in his misery fully conscious.

He'd found that the cracks in his arms made it so there was enough space to dig in his bony fingers and pull at the outer layer of the membrane. That with enough force and time, the white bone could flake off until the inside marrow was exposed. And once that pink marrow on the inside was exposed, that was when the hurt would set in.

It was painful. Very painful. That was no surprise. "Chipping" was nothing more than literally him tearing his own bones apart, exposing the weak insides of his arms. But... it felt good. Not because of the pain that came with it- no- but because it was the one pain Sans could control. The one time where the skeleton could stop the pain when it got too bad. The one time Sans had control of his own body and it wasn't being used by someone else. If it was just pain he wanted, then he could always just wait until the nights when his Boss got drunk or angry at him. That would bring the hurt right to him.

That wasn't the only reason he did though. There were other things the chipping accomplished besides the illusion of control. It kept Sans' hands busy and made sure he stayed grounded, his thoughts never straying too far.

Sans was aware it was a bad habit. Hell, he'd even tried to stop himself a few times. It couldn't be good, stripping the protective structure around his arms like this. It just left him exposed and weaker than he already was- and with his pathetic one HP and defense, that wasn't something he could afford to do. Yet the skeleton couldn't bring himself to stop. After every violent night of abuse and cruelty, his hands would always find their way back to the familiar cracks and cuts. Whether he meant to do it or not, his fingers would start to dig into his bone, falling into their regular pattern.

Like right now. Sans hadn't even realized that he'd pulled the black sleeve of his jacket up and his fingers were already tracing the inside of the cuts in the usual fashion. He moved from the deepest cracks- the ones closest to his wrist- back further, where his bones had healed over previous cuts as well they possibly could, the messy system of cracks still marking the spots.

It wasn't pretty. The bone was so cracked and chipped that it was almost unrecognizable. Sans couldn't even remember what his arms had looked like before he had started chipping. It had been so long that he couldn't even imagine it.

 _I'm going back._ The realization was hardly shocking _._  It wasn't something that was up for debate. He couldn't stop it. This Undyne and second version of his Boss were already building the machine to send him back. Within maybe a few more hours, he'd be back in his familiar Underground. His familiar, cruel, heartless Underground, with a brother who didn't care in the least about him and would probably punish him for his disappearance. Trapped in a trans-universal mix-up or not, the Boss didn't like losing his pet. Not even for a day.

Soon he'd be back home. Where he would be expected to forget this whole thing. Sans found the very notion ridiculous. How was he supposed to forget this? This seemingly perfect version the Underground, where everyone was nice and friendly? Or at least, more so than the ones in his timeline.

This place had been everything Sans had ever hoped for. An Underground without the abuse. Without the torture and cruelty. A place where he could live his life as a monster and not just the property of someone else. This entire universe represented Sans' one dream. His one desire. And it made him absolutely sick to his nonexistent stomach.

Because now that he had seen this place for himself, and had met some of the monsters here, he was more than convinced that this whole thing was real. Not just some delusional fantasy created by his mind as a means to cope with his miserable existence. This was real. It existed. And he was standing in the middle of it, right now.

And he wasn't allowed to have any of it.

Sans didn't know what he would do once he got back to Boss in his timeline. Maybe he'd finally lose it. Maybe he'd snap and end up getting himself killed. Maybe that was for the best.

How exactly was he supposed to keep going on with his old life like nothing had changed, when very clearly,  _everything_ had changed? How was he supposed to keep himself together with the optimistic idea that one day, things would be better, when he already seen the "better?" This was exactly what he wanted, and he wasn't allowed to have it. How was he supposed to just forget about it?

 _It's for the best._  Sans soured at the idea, but he couldn't disagree with himself. He didn't deserve a life like this. Sans knew that. The things he'd done... why would they be rewarded with something like this? He was just a screwed up as every other monster in his universe. Maybe even more so than a lot of them. The skeleton wouldn't belong here. Besides, there was another version of him out there, in his universe. One that really did belong here. A Sans that was good and deserved all these great things that he did not.

Sans sighed in exasperation, slumping back into the wall and beginning his chipping with a new spot on his ulna. He needed to take his mind off of all of this. Sans shouldn't even being worrying about all this. He had no choice in this matter. This other Papyrus would force him to go back even if he didn't want to- he was concerned about his actual brother. Not some alternative reality's version of him.

Like always, it took a few minutes before the outermost casing flaked away, but after that the process was underway, and the pain and the sweet relief it brought swept over the smaller skeleton, providing him with a good distraction from anymore thoughts.

His fingers worked their way at the bone masterfully, the muscle memory of the action kicking in. Layer after layer continued to chip away as the time wore on, and the deeper he got, to more painful it became. Every scrape and pick began to send the familiar stabbing sensations down his spine. Sans gritted his pointed teeth hard as the pain wove through him. Yet the hurt didn't stop him from digging even deeper. Sans knew that if he stopped than there would be nothing to keep him from his thoughts, and he couldn't let that happen.

Once his chipping began to hit the weaker bone towards the center of the structure, Sans knew he was getting close. Just a bit more and he'd reach the center of the ulna. After that, he could move on to his radius. And if the skeleton still needed a distraction after that, he still had two bones on his other arm. He could dig into those-

"Just stop, okay?" The sudden order caused Sans to jump a bit- the voice of the scientist had been the first thing to break the rhythmic beat in the room from the two monsters tinkering with the machine. "Just stop." 

Sans froze. The other monsters had seen him? Sans had lost all sense of the world around him. The skeleton had no clue how much time had passed since he had begun chipping, or if the others had been paying any attention to him. He opened his mouth to respond and say something, but the larger skeleton beat him to it.

"Don't be ridiculous Undyne. I'm not stopping until I see my little bro back here, safe with me," Once Sans heard the orange hoodie wearing skeleton reply defensively, the realization that the Royal Scientist wasn't talking to him hit the other skeleton. Sans relaxed back a bit and let his mouth fall closed once more, knowing he was fine. His fingers unconsciously continued their chipping along the newly exposed portion of the bone, yet the pain faded to the background of Sans' mind as he listened in on the argument the other two monsters were having.

"I get it," Undyne seemed pretty tired. "But you need to listen to me. You haven’t paused since we've started working. It's been twelve hours Papyrus."

 _Twelve hours?_ Had it really been so long since they'd been down in this lab? Sans knew it had been long, but he didn't think it had already been half a day. Boss was going to tear him to shreds when he got back.

"Just... stop for one moment. Take a little break. It'll help you focus."

"No time to relax," Papyrus insisted, shrugging the other monster off. "We can't waste a moment."

"I'm not saying it has to be for long. Just a short while. Please," Undyne was begging the larger monster. "Just do this and I'll stop bugging you."

The unhappy expression on the larger skeleton's face made it pretty clear that he wasn't happy about the scientist's order, but Undyne didn't seem like she was going to back down. Both monsters engaged in their private staring contest for about a minute, until Papyrus finally looked away, an angry snarl painting his face.

"Fine. But five minutes only," He muttered, moving on his way to the exit of the room.

"Thank you," The Royal Scientist seemed relieved. Sans couldn’t understand why she seemed so concerned about the larger skeleton.

Papyrus made his way out of the room, digging through the pockets of his old orange hoodie until his bare, bony hands grasped the small carton of smokes. The larger skeleton pulled the pack out, along with a small metal lighter, as he made his way out of the room. He placed a cigarette between his teeth and moved his lighter up to light it, but stopped in his tracks as he saw the smaller skeleton sitting next to door.

Sans' hands had yet to move away from the cracking and the exposed marrow of his chipped arms, and the skeleton's sleeve was still pulled back, letting the larger skeleton see everything; every self-inflicted cut and crack, the pink marrow, and Sans own fingers paused in the middle of the action, not sure what to do once they were caught. The larger skeleton could see all of it.

Neither Sans nor him said anything at first, with the larger skeleton only looking down at Sans and Sans looking back up at him.

Sans eyes were full of that rebellious gleam they usually held whenever his Boss caught him doing something he wasn't supposed to be doing. It almost seemed to shout, " _So what are you going to do about it?"_ at the other monster.Of course, that rebellious look of Sans was nothing more than a fake show he put on. Something for the skeleton to hide behind and conceal the fear inside him- fear, because he knew  that nine times out of ten, disobeying Boss would lead to some form of punishment.

Of course, this wasn't Boss. This was some alternative version of Sans' brother from another universe. Yet they looked so similar that the initial reaction was impossible to resist, the fear and terror wrenching at the skeleton's soul too strong to stop.

For a moment- just one short moment- it looked like this other version of Boss was going to say something to him about the chipping. That maybe he'd finally acknowledge Sans' presence in the lab. Maybe he'd tell him to stop, or ask why the hell he was doing it in the first place. Sans wouldn't have much of an answer for the larger skeleton if he asked why. This Papyrus would probably think he was crazy if he told him it felt good. And if he told him to stop, there was no way the smaller skeleton would be able to do so.

Yet in the end, neither of those things were the case. The larger skeleton clicked on the lighter in his hand and looked away from the other version of his younger brother, as if there had been nothing to see. He pretended like he hadn't just witnessed the scars and cracks that the smaller monster had given to himself over years of self-torment.

The small controlled flame that began to burn brightly was brought to the skeleton's mouth, where the stick held between the two rows of teeth was lit. Then, without saying a single word to the other monster, the Papyrus walked out of the room, already taking a drag on his cigarette.

The larger monster may have cared about  _his_ Sans, but that was all. This Sans from another timeline wasn't his own Sans, so he wasn't his responsibility to look after. And Sans understood that.

* * *

“Look who's finally up,” The other monster pushed a cart before her as she entered the room. The skeleton was still lying on the table bound, with wet streaks running down his face. “Is that tears I see?” It was a rhetorical question, and the smaller monster didn’t respond to it either way. “How predictable.”

Sans could hear the furious scribbling on the doctor’s part- a pen running roughly across a pad of paper lying on the cart. It appeared she was taking notes- like she was examining him. But the way she was doing it, with a perfect calmness and no emotion in her voice or actions made it pretty clear that she didn’t care in the slightest about the skeleton. The scientist was looking him over like she had when he had first come into the lab- as if he wasn’t even a monster; like he was some sort of… experiment.

“What are you doing?” Sans couldn’t even recognize his own voice as he said the words. It sounded so frail and broken. The energy and happiness that was always bursting inside the skeleton wasn’t there- replaced with an empty emotion that Sans couldn’t quite place.

“Making notes on your current state,” The other version of Alphys didn’t even pause for a moment before spitting the answer out as if it had been obvious. “Your reaction is fairly standard- just some mild symptoms of shock.”

“My reaction? To what? Getting my skull smashed in with a hammer?”

“No,” There was a momentary pause. “Well, yes, that too.”

 _What’s that supposed to mean?_  Sans wondered to himself. Before he could ask the question to the other monster however, Alphys stepped next to his table and picked up his skull. Sans flinched at the sudden movement, and inhaled sharply at the pain that ensued. Moving still hurt very much.

The scientist traced her gloved fingers across the back of his head, right across the injury. Sans could feel the fractured bones from the injury caving inwards in his skull, and it wasn’t a good feeling. His entire head felt like it was threatening to collapse from the lack of support along the back of his skull.

“I was testing your reaction to pain,” The scientist decided that only after she had let Sans’ head smash back to the hard table would she elaborate on her previously seemingly contradictory statement. “I was curious as to how a monster like you would react to the feeling. You’re clearly a monster who is unfamiliar with intense familiar physical pain- judging from the lack of scarring and cracks. In fact, you said you had never even broken a bone before- something that I found quite surprising.  I knew your response to any form of pain would be quite intense, and I couldn’t help but wonder how it would be.”

There was silence for a moment, and the scientist began to return back to her notes when the skeleton spoke out once more. Sans’s response was one of utter confusion and disbelief.

“You broke my skull because you were curious?”

“Pretty much,” There was no sign of hesitation on Alphys’ part before she answered the question. Even after she had spoken, she continued on with her notes.

 _Unbelievable._ How was this monster so calm and open about something like this? She had nearly killed Sans. The scientist was treating Sans like he was some test subject and not some fellow monster. How could she justify those actions by saying “she was curious?” How could that possibly make it okay to do something like this?

“You’re insane,” Sans had never called another monster an insult like that before. He was above such petty behavior. But he was serious about this. He was more than convinced that this monster had lost it and gone full on psycho. “You’re absolutely crazy.”

“Correction,” Sans could hear the scientist’s pen falling back to the pad and he glanced to his left the best he could without moving his skull and causing any more pain than he was already in. Alphys had stopped her notes and was staring right at him. “I am the Royal Scientist. And I’m only doing my job.”

Sans didn’t believe the statement for a second. He may not have been one to understand all of Undyne’s science stuff back in his Underground- or well, any of it for that matter- but he was more than sure that none of it had involved using violence to satisfy the Royal Scientist’s own curiosities. Or any violence at that.

“The Royal Scientist is supposed to work for the greater good of all monster-kind.” This hardly seemed to be anything close to that. Helping the whole of the monster race was pretty far off from kidnapping unsuspecting monsters by knocking them unconscious.

“Only in the fairy tale of a timeline you seem to be from. Things are a bit different here.”

“But why?”

“Because they are.” The scientist stated the answer so matter-of-factly that it seemed like she was sure that was the way it was, and nothing could change that.

“But why?” Why couldn’t this timeline be like his own? Why wasn’t it?

“Because I said so- now shut up.” The other monster’s calmness broke as she snapped at the smaller monster, as if he had struck some sort of nerve. “Unless you would rather I resume my testing?”

The threat of being hurt was more than enough to make the skeleton return to his previous silence, and the scientist’s anger disappeared as soon as it had arisen, and her infuriating calmness was back.

Of course, Sans had never been one for silence. The room remained quiet as the crazed doctor continued on with her observations for just a few minutes, before the skeleton took it upon himself open his mouth once more.

“What happened to you helping me get back to my timeline?” The skeleton held little hope of this Alphys actually helping him get back to his home, but he felt like he needed to ask.

“That was never going to work. I could work on it for years and still make no progress. Timelines aren’t of such a simple matter. It’s not as if someone could just build a machine and traverse through them at will.”

 _If that was the case, then…_ “You never had any intention of helping me… did you?”

“I can’t say I did,” She was still as calm as ever, and there wasn’t even the single trace of guilt in her voice.

“Oh,” Sans’ eyes trained on the ceiling as his voice broke partway through the word. “I see.”

 _I’m an idiot. A fool. A blind, stupid fool._ No wonder everyone in his Underground never took him seriously. No wonder his big bro didn’t trust him with his secrets. Because he was dumb. Blatantly stupid.

Sans hadn’t ever thought he’d been the smartest monster in the room. Sure, he couldn’t understand his Royal Scientist friend’s science stuff, and sometimes he had trouble learning fighting tactics from Alphys. And maybe he struggled to read anything other than the picture books on his bookshelf, but that all hadn’t meant he was an idiot. Just that he wasn’t the brightest monster.

But now it was clear to the skeleton just how  _stupid_  he was.

 _I thought I could find my way back to my home in my Underground. That I could just cross through this cruel reality to Undyne’s lab and get her help to fix this whole thing._ Even though all the monsters here had either tried to kill him or been unwilling to save him from being killed without something being in it for them, Sans had assumed that the Royal Scientist would be different. That even though this universe was full of monsters that were mean and rude, she’d be different.

He thought that he could at least trust this universe’s version of one of his friends, yet he hadn’t even been able to trust this Underground’s version of his brother. It had made no sense, but Sans had been too blinded by his hopeful, optimistic vision of everything to see that. Like always.

_I thought that once I made it to this lab, all my problems would magically disappear. But now they’re just worse._

He was such a fool.

“Back to the tears I see,” The wet streaks down his cheeks were glistening in the dim light of Sans’ eyes. Alphys only scribbled down more notes on her paper. She made no move to calm him- no attempt to comfort him. A part of Sans had expected her to. Usually any monster- even a stranger- would go out of their way to help another monster.

But the other half of the skeleton- the same one who had just now realized how stupid he was- was starting to know better. The monsters here weren't like the ones in his Underground. They didn't care. They didn't even pretend to care.

“How can you be so calm?” Sans was choking back the sobs that were threatening to break out. “How is it you can act like…  _this?_ ” The skeleton blinked the tears away. He didn’t want this other monster to see him cry anymore. He needed to be done crying. “I… I just don’t get it.”

"Getting emotional is a distraction from the task at hand,” The scientist explained. “In my line of work, distractions are something I can't afford to have."

"So... you separate yourself from everything? From all feelings and emotions..." _...from any sense of humanity and justice? Or what is right?_

"It probably sounds hard to someone like you, but it’s something that had to be done. You've got to remember that this isn't your timeline. Here, it's every monster for their self. Though I do have to admit, it does gets easier as time goes on.”

"So I guess I’m not the first monster you've done this to?" Sans hadn’t thought he had been, but this was just a confirmation.

“Please. As if," The scientist snorted. “I’ve seen monsters of all sorts. Even ones like you, in this Underground- it makes me wonder how they possibly could’ve survived for so long. Dumb luck, perhaps.” Alphys paused for a moment. “But, you are the first one from another timeline. I thought experimenting on you might prove to be quite interesting.”

The way the doctor talked about him made it clear that to her, Sans was nothing but another interesting test to run. Another experiment she couldn’t wait to see the results too.

“How can you live with yourself? I mean- I could’ve… you could’ve killed me, and you don’t even care? You don’t even seem fazed by the idea," How could she ever justify something like that?

“Well, maybe that’s because I did kill you.”

 _Wait._  Sans shifted his head ever so slightly, facing the monster despite the pain it caused.  _What?_

The skeleton didn’t think he’d heard her right. He couldn’t have heard her right.

Just by looking at the confusion on the skeleton’s face, Alphys was able to guess what the skeleton's thoughts pretty well.  Sans didn’t even have to open his mouth to ask the question before she answered it.

“When I first attacked you, I hadn’t been aware that you had such a low HP. After being hit with the hammer, your HP fell below zero and you fell down. Fortunately for you, I was able to stabilize you before you turned to dust.”

“Stabilize?” Sans felt lost. He had died? “How?”

“With this,” The scientist pulled a small syringe from the top of the nearby cart. She tested the needle by flicking it with her gloved finger, and as she did so, the red liquid inside the container sloshed around.

“And what is that?” Sans’ eyes warily stared at the syringe. He didn’t like the look of the liquid inside. Nor the sharp pout of the needle.

“This," The scientist turned the container in her hands, admiring it. "Is human Determination. Or, more accurately, an extraction of human Determination. It is used by humans to keep them going. It’s their secret weapon that makes them so hard to kill,” The scientist explained, still memorized by the substance. “All I needed to do was inject a small amount into your soul after you fell down.”

Sans winced at the thought of stabbing his soul with the sharp needle point of the syringe and injecting the “Determination.” He couldn’t help but be thankfully that he had been unconscious/temporarily dead when it had happened.

The doctor held the tool out to the skeleton to see. A little bit more than half of the container was filled with the red liquid. “This is a 3 milliliter dosage. “

“Is that… a lot?”  Sans was far from familiar with the substance. He had no clue what was “too much” or “too little,” because up until five seconds ago, he hadn’t even been aware that there had been a substance that could bring fallen down monsters back to life.

“For a human? No. Of the human souls King Asgore has collected thus far, they all produce nearly twice this amount in a single day. Now, as for a monster…” Alphys smiled unnervingly in thought. “This is certainly more than any monster dare inject themselves with. Excessive amounts of Determination present in the bodies and souls of monsters make the emotions and thoughts of said monsters unbalanced. If the recipient is not prepared in the right ways for the injection, then the Determination could prove lethal. The substance could even cause the monster to melt before their very eyes.”

Sans eyes widened in fear. Of all the ways to die, melting slowly was probably his  _least_  preferred to go out. The scientist had said that the amount she had injected into him had been a small one, but this Alphys was insane. She may have lied for all the skeleton knew, and he might start melting any moment now. What if she had done that as another test of hers? What if the doctor had been “curious” as to what he would do if that started happening to him?

“But your soul wasn’t like the other monsters,” The doctor began to tap one of her clawed fingers against the cart, producing a steady, rhythmic pattern. Her eyes were looking off past the skeleton with a wild expression in them that Sans didn’t like in the slightest. “No. Your soul was different. Something about it makes me think your experiments will be quite different from the others.”

“Wh- what is it?” Sans asked. He was scared as to where this conversation was going, but he couldn’t quite understand what she was talking about. How was his soul different? His soul was normal. Or at least he thought so. The only souls he'd ever seen were his own and Papy's. And his looked nearly identical to his big brother, only blue instead of orange.

“Your soul isn’t that of a normal monster. Yours already had a small amount of Determination present in it- which is unheard of. Because no monster’s soul can make their own DT, no, only human souls can do that,” The monster’s tapping was beginning to speed up, as if the idea was so fascinating to the scientist that it was pushing her to the brink of bursting in excited. “Except your soul wasn’t just previously injected by the substance- your soul had no markings to indicate anything of that sort. No, your soul was built around the substance.”

“Built? What do you mean my soul was built around it?” How could his soul- or anyone’s- be built? Souls were formed from the magic of a monster’s two parents. And while Sans hadn’t ever known his parents, he had always assumed that they had been very nice and had a perfectly good reason for leaving Papy and him on their own.

Yet the way this Alphys made it sound… it seemed like he didn’t ever have _real_ parents. That his soul was made… differently.

 “I mean your soul wasn’t naturally produced. The magic inside is concentrated in such a way that means it must have been formed through other means.”

“Other means?”  _Not naturally produced?_  Sans head was swirling in confusion. What the scientist was saying wasn’t making sense to him. “What are you talking about?”

“Your soul was artificially created,” Alphys’ tapping was so fast and hard now that Sans couldn’t help but think that she must be chipping into the cart with her gloved finger. “It appears to have been designed so that it can contain human DT safely.” The scientist looked back to the syringe in her other hand. “Which means that this amount of the substance- an amount that no other monster could possibly hope to survive- can be injected into your soul.”

 _Artificially created?_ Sans could hardly understand what the scientist was saying. How could his soul be unnatural? How could it have been created in any other way that was normal?

“The question is, what will happen? What happens when the Determination in a monster’s soul reaches a level closer to that of a human soul?” The wild look in Alphys’ eyes was still there as she turned back to the captive skeleton. “Well, that’s what I intend to find out.”

It took a moment before what the scientist wanted to do was processed in Sans’ mind, but once it did, Dr. Alphys was already beside him at the table, syringe in hand.

“No!” Even though he was still bound by the metal chains, Sans began to flail wildly under the scientist’s grasp. The pain that followed the movements burned through his body and made him want to scream. So he did. He screamed as loud as he possibly could, but didn’t stop his flailing. He couldn’t let the scientist inject the substance into his soul. There was no knowing what that much DT would do. Artificial soul or not, Sans didn’t trust this scientist for a moment. He couldn’t let her do this. He wouldn’t.

But even with his flailing and screaming, he was powerless to stop the Royal Scientist. She was stronger than he had expected, and her gloved hand had no trouble pinning his neck down to the flat table. The green shirt the skeleton had woken up in was ripped up, exposing his rib cage and the bright blue glow of his soul.

The skeleton’s breathing became strained as he felt a red glove clamp hard around his soul. It felt like his very essence was being suffocated under the grip of the other monster. It hurt. Even worse than his broken skull.

He watched, unable to do even the slightest thing to stop the scientist. He continued to twist and scream and shout, but all his pleas fell on deaf ears. The scientist didn’t care as to what he wanted. All she was concerned with was using him as her experiment- and she was using his own soul as just another tool to force the skeleton to feel pain.

Sans’ soul was a bright blue- just like his eyes. It was perfectly smooth and unmarked. Or at least, it had been the last time the skeleton had seen it. Yet now it had a small circular mark along its side, where the scientist had injected the Determination the first time.

Alphys inserted the point of the needle right next to the other mark, and Sans let out another scream of pain as she stabbed into soul. The scientist began to inject the liquid, pressing down on the end of the syringe. Sans could feel the foreign substance spreading into soul.

“Please… “ Sans’ voice was so weak that even he couldn’t hear his own begging. “Stop…”

But the doctor did no such thing. She injected the rest of the substance into Sans blue soul, and the small skeleton could feel the pain spreading through not just his bones and limbs, but through the very essence of his being as well.

* * *

The warm puff of smoke left the skeleton’s mouth as he breathed out in a sigh, almost immediately cooling in the frigid air that surrounded him. The rush of the nicotine, coursing through Papyrus’ insides to his soul was just what the skeleton had needed.

Papyrus was the first to admit that he wasn’t the best with stress. Try as he might to work his way through it or battle against it, stressful situations were not something the larger skeleton handled well. He didn’t melt under pressure per se, but it certainly left him on edge. Papyrus knew that in stressful situations like this one, his emotions got a bit cramped. He started to act nothing like his usual self, instead getting cranking and upset and set off by the smallest of things- making him not the easiest monster to work with.

Papyrus didn’t like to admit how much he needed his smokes. The cigarettes were the one thing that allowed him to maintain his composure and keep his cool. The familiar feeling of the smoky taste settling in his mouth was just what the skeleton needed to get through stressful situations. Not to mention the fact that he had come to rely on the small packets more than he’d like to say.

 _That’s addiction for you._  The chuckle that slipped from Papyrus’ throat without him really even thinking about it was empty, with no real humor or amusement in it. The smoke from the cigarette drifted out of his mouth as he did so, its warm feeling abandoning the skeleton.

The skeleton had ported to somewhere in the middle of Snowdin’s forest. Papyrus hadn’t been paying too much attention as to where exactly, letting his body complete the mindless task without much guidance. He’d long since mastered his shortcuts- the magical teleporting that tore through the fabric of reality.

Undyne had forced him to take a break. It was just for a moment, but Papyrus wasn’t very happy about it. He knew he was wasting time, sitting out here in the middle of Snowdin like this. He knew he should still be in the lab, working on the machine. But the Royal Scientist wasn’t going to stop bugging him until he stopped to catch his breath- and frankly, Papyrus knew he could use the moment of rest. It at least gave him the chance to have a smoke and calm his frayed nerves.

Papyrus didn’t smoke inside, not anymore. He could thank his little bro for that. Sans always forced him to smoke outside. Snowdin could be in the middle of a blizzard and the skeleton’s house door could be snowed in, but that didn’t matter to the smaller skeleton. If Papyrus wanted something to settle that feeling that started to eat away at his soul whenever he went to long with the cigarettes, he had no choice but to make his way out to the chilly outdoors and light up one out there.

The larger skeleton didn’t get upset at his bro for acting like that. He could never really be mad at his Sans. Papyrus knew that Sans wasn’t just being strict for the sake of it. The larger skeleton knew that his brother genuinely thought that if Papyrus had to freeze his bones off to indulge in his habit, that maybe it would lead to him quitting.

 _Of course, that would never be the case._  He let his long bony fingers fiddle with the cigarette, his eyes memorized by the burning end of the stick. The skeleton had no idea how he’d get through some days without them. Papyrus brought it back to his mouth once again, inhaling deeply before the familiar rush took him over, like always. It made him feel alive.

 _Sans always hated my smoking, huh?_  The smaller skeleton used to complain about the habit constantly. In reality, Papyrus doubted Sans knew how much he needed the cigarettes. Not just because of his addiction, but because he was scared as to what might happen without them.

The thought of the younger skeleton’s distaste for Papyrus’ bad habit was enough to remind Papyrus of the dilemma that they were all currently stuck in. His next drag from the cigarette didn’t make him feel as good as the previous ones did. Sans was probably in mortal danger, and here the other skeleton was enjoying the smoke in the middle of the woods of Snowdin. Papyrus could feel the guilt of his actions crawling down his spine, even if Undyne had forced him to take said break.

 _I’ll just finish this cigarette,_ Papyrus decided, bringing the smoke to his mouth for another drag as he scowled off in the distance at nothing in particular.  _Then I’ll head back to the Lab._

Being back in the bottom floor of the lab wasn’t something the skeleton was so eager to do. It had been years since Sans and he had been there, and a lot of the layout had changed, but the bad memories the skeleton associated with the place were still there. Being back in that place stirred up thoughts and memories in Papyrus’ mind that the skeleton would much rather leave buried, but no amount of past recollections would stop him from working in there if it meant saving his brother.

 _Seems like keeping him safe is always a concern of mine, isn’t it?_  Even without having to worry about timeline shifts that put his Sans in danger in a malevolent Underground, Papyrus still had to worry about the constant threat of the resets.

He could feel the worry starting to form knots in his soul, and Papyrus stopped himself before his thoughts could go any deeper. He had enough on his plate right now without bringing  _those_  into this. Papyrus exhaled in a sigh, more smoke coming from his mouth. It would be better to think about something else. Anything else but the resets.

It didn’t take long for his wandering mind to reach a new topic. Of course, it was the one that was probably the most glaring in the skeleton’s mind, as well as the thing he had been trying his best to avoid. The one thing that was still on his mind after seeing it happen back in the lab, right before he had left.

 _I should have said something ._ Papyrus tugged the cigarette out from between his teeth as the guilty thought crossed his mind, despite how hard he had been trying to ignore it.  _I should have said anything._

Papyrus could feel his own arms flaring up in sympathy pain, reminding him of just how much pain the other Sans was probably in. How much pain the other Sans had been inflicting on himself.

_How could I just let that happen? How could I just not say anything?_

Sans- his Sans- would be so mad at him for ignoring something like that. He always thought that they should be nice to everyone. That they should take it upon themselves to help everyone.  If Sans knew Papyrus had ignored a problem as big as that one…

Even without the thought of his own brother’s reaction to the scenario, Papyrus still felt guilty. The other skeleton had literally been cutting into himself, digging into the bones of his arm. The cracks over his arm had covered the entirety of the bone. This hadn’t been a one-time thing for the smaller skeleton. This had been something the other Sans had been doing for years.

 _That’s this Sans’ way of dealing with things._  Papyrus could relate. He had his smokes, his Sans had his puzzles and games and books, and this Sans had… that. It was a lot more extreme than puzzles, sure- but then again, this Sans very clearly had a life that was much harder than anything Papyrus had ever had to live through.

Every day was living hell for this version of Sans. Constant abuse, cruelty along with other things that Papyrus didn’t really want to think too much about. This Sans had to find some way to hold himself together. It just so happened that was how he did so.

 _Maybe I should just let it go._  Papyrus felt his bones crawl at the very idea of doing something so… awful. How could he just turn his back on this monster that was clearly in so much pain? And the fact that he looked just like his Sans- only lonely and miserable and  _so broken-_ wasn’t helping Papyrus. It felt like his worst fear, seeing his brother in a state of such misery. How could he turn his back on that?

Yet Papyrus already knew his answer. He could ignore something like this-  _would_ ignore something like this, because if he said anything- even the slightest words of comfort- he would end up getting involved. Involved with this other Sans, with his timeline, and his problems. Doing something like that would only complicate everything. All that needed to happen was Papyrus and Undyne finishing the machine and fixing the timelines so they could get their Sans back. After that, they could drop this issue completely.

If Papyrus started getting invested in this other Sans, the only thing that could lead to was more problems. More issues that needed fixing and made everything way harder than it needed to be. It would best- for everyone involved- if they got this all done as fast as possible, while saying as little as possible about the whole situation while doing so.

The idea didn’t settle well with the skeleton. It felt so… wrong. His timeline or not, Papyrus didn’t like the idea of treating any version of his brother so poorly. He loved his Sans so much. It felt weird not trying to help, not saying anything. It felt awful.

But… it was for the best. It was what needed to be done. It was the best way to make sure his Sans got back safely. He couldn’t make anything more complicated than it already was. He couldn’t afford to do so. This was the best course of action.

Papyrus took a final drag from his cigarette before throwing it to the snow below him. He’d gotten too lost in thought. He should’ve been back at the lab already.

The skeleton snuffed the end of the burning stick out by kicking the snow over it with the white ends of his orange sneakers, effectively burying it.

 _Time to get back to work._  The air around him began to shift like always as he began to teleport his way back to the lab. He could see his surrounding begin to fade away into a thick haze, until it all refocused and he was back in the poorly lit hall at the bottom floor of the lab. Casually, the skeleton strolled back down the hallway and into the room where Undyne and his brother’s double were.

“Guess it was too much for me to ask you to take a break longer than a few minutes?” Undyne didn’t even have to turn to ask the question, sensing the skeleton’s presence in the room as soon as he entered. The scientist was on her knees right in front of the machine, working on some wiring.

“You guessed right,” Papyrus quickly scanned the rest of the workroom. The piece he had been working on was still at his table. As for the rest of the room… well, Papyrus hadn’t realized just how in ruin the place was, with metal scraps and parts littered randomly across the room.

Papyrus wasn’t a fool. He knew this whole thing had been a giant shit show. If only Undyne and he had a bit more time, they could probably make the whole thing a lot better. Unfortunately, time was one of the things they did not seem to have nearly enough of. Not a single moment could be wasted, not a second spared. The constant clock of pressure was ticking away, and every moment when Papyrus’ bro could be in potentially life-threatening danger.

It was hard to believe that this would work. That a machine like this even had a chance of doing what it was supposed to. Papyrus had to admit that this whole thing was a longshot. After all, he knew Undyne had been right earlier. They didn’t have a plan. They didn’t have a good idea of what it was they were working with here. They didn’t even fully understood  _how_  it was that the timelines worked.

But Papyrus knew this would work. He wouldn’t be abandoning his brother anytime soon, not when his Sans needed him. The larger skeleton was positive this would work. It would work because it had to work.

The taller skeleton’s eyes landed on his brother’s copy without him really even meaning anything by it. The other Sans was still sitting in the same corner of the lab he had been in no more than a handful of minutes ago. His black sleeve had been pulled back over his arm, hiding the cracking and chipping along the bones of his arm.

 _Don’t mention it._  The look in the other skeleton’s eyes was pretty clear. They didn’t want to talk about it anymore than Papyrus did.

“I think it’s almost ready,” The scientist pulled herself from the floor, moving to another part of the machine. “Well, actually- I  _know_  it’s almost ready.” Undyne tried to clean the smudge on her glasses with the sleeve of her white lab coat that was stained gray in some spots from working in the lab all day. “All we have left is hooking up the part you’ve been working on and finishing up the wiring.”

“And then?” Papyrus doubted that was it.

“…then, all we need to do is fix any parts that aren’t working like their supposed to and run a few checks to make sure everything is in working order. After that, we can try to do this.”

 _The question is, will it work?_  The unspoken words hung over the room, not needing anyone to voice the doubts.

“It will work,” Papyrus was sure of it. Just hearing himself say it aloud made his feel absolutely convinced. The feeling in his soul from earlier was back, burning inside of him. The same exact feeling that had convinced him earlier that this whole thing was possible.

 _This will work._  It would.

“Well let’s finish this thing up then,” Papyrus nodded in response, heading back to his worktable. They were almost done now. All that needed to happen was that Papyrus needed to finish his part of the machine, and the Royal Scientist needed to connect wiring and check over what they had already.

_This will work._


	9. Chapter 9

**Summary for the Chapter:**

> Underswap Undyne and Papryus manage to finish their machine, but run into one unforeseen difficulty. Underfell Sans runs into a problem of his own as well.
> 
> At the same time, Underswap Sans finds his own way to deal with the dark lab he's trapped in.

**Notes for the Chapter:**

> Guess who's back! It's been over three weeks, but here it is, chapter 9!
> 
> Once again, each scene alternates timelines. And also once again, I ended up having to cut this chapter in half once more. Unless everyone wanted to wait another week or two for the full thing, I decided that this was better for everyone. So that means next chapter will be both Underswap and Underfell as well.
> 
> Either way, please read and enjoy!

Eventually a monster reaches past the threshold of the pain they can withstand- the max amount of hurt they can take before the feeling finally becomes… nothing. When the monster becomes so acquainted with the experience that it begins to feel numb, the sensations overloading their mind, frying it so that there could be no more pain for them to take. Not because the feeling was really beginning to dull, but because the monster could literally take no more of the physical abuse, and that part of their mind had no choice but to completely shut down.

Sans was starting to wonder when exactly he would be at that point. He would definitely welcome anything that dimmed the pain.

The skeleton pushed himself over, rolling his limp body over onto his back. He was alone again, tossed onto the floor of the room after he had blacked out during the injection.

Sans’ wrists no longer were chained by metal cuffs. _At least I’m free._ The skeleton tried to stay positive, but he didn’t think “free” was the word for it. He was still trapped in a dark lab by a crazy monster in a universe that he couldn’t get back to his own from. If anything, he had broken out of one cage only to be stuck inside another- which was encased in an even bigger cage, one that Sans had little chance of escaping from.

Did it even matter that he was no longer chained? Sans doubted he could even stand. The pain he was in was so bad that he couldn’t even think straight. Even lying motionlessly on the floor, the skeleton had to fight for every wheeze and gasp of air he could get.

It hurt. Even worse than when he’d woken up for the first time in this cursed lab. It hurt so bad that Sans couldn’t even find any other way to describe it. The pain he’d experienced from having his skull broken in had been more horrible than anything he could’ve ever imagined. The only way Sans could describe this was that it was even more awful than that.

Everything hurt. Every bone ached. The whole of Sans’ body shook uncontrollably with every spasm of pain. It was terrible. Yet Sans’ soul had to be the worst of it.

 _Is it even my own?_ Sans could feel the blue organ hammering away in rib cage. A steady drum beat, with each pulse the soul threatening to burst. It didn’t feel like his soul anymore. It was strange and foreign, just like the red liquid coursing through it.

He didn't get it. Sans’ blue soul had always felt warm to the skeleton. Like a comfortable melody, or one of the stories Papy usually read to him before bed. Whenever the skeleton’s soul beat in his chest, it was filled with magic and life and radiated pure _joy_ through Sans’ body.

So where was that magic now? Where was that positivity that would help him get out of here? Sans knew he could certainly use the help, but his soul just seemed stagnant and cold in his chest. Like it was completely… empty.

The soul in his chest, beating emptily with no real purpose... it wasn’t really his. It couldn't have been the same as Sans' soul. It was something completely new, completely different. It felt like it was tearing apart in Sans’ rib cage, almost as if at any second it might shatter and Sans might turn into a pile of dust.

It’d been too much. The injection- the Determination- Sans knew he couldn’t handle it. He couldn’t handle something like this. It was just too much. He couldn’t do this. His bones were already starting to crawl with the thought of himself melting into nothing more than a puddle. That’s what Determination did to other monsters. That’s what this maniacal version of his Alphys had told him. That monsters weren’t supposed to handle the Determination. That it made them unstable. That it would kill them.

Except he wasn’t like the “other monsters,” no- he was _special,_ wasn’t he? He wasn’t normal. His soul was different. He was different. He was _special._

 _Is this what special feels like?_ Knowing that he should be dead, or dying, but wasn’t? Knowing there was no end in sight for him and this pain. Knowing that he very well might be stuck in this place for the rest of his life. Because of Determination. Because of a will to live that wasn’t even his own- one that was instead stolen from some imprisoned human soul.

Determination. How ironic it was that the thing that was clawing and burning at the insides of his soul, was the very reason that he was alive. That very thing causing his pain was also the thing that kept him alive to experience it- to live through every torturous moment.

It didn’t make sense. But then again, none of this did.

 _“What did I do?”_ Sans didn’t expect an answer to the whispered question as it echoed softly throughout the empty chamber. _What did I do to deserve something like this?_ Sans wasn’t a bad monster. At least he didn’t think so. So what could he have done to be tortured like this?

It wasn’t fair. It wasn’t fair that he had to be ripped from his own Underground- from the arms of his loving and caring brother to this universe, and thrown into this one. But yet again, in the life lesson that this whole experience was hammering into Sans’ skull- sometimes literally- life wasn’t fair.

Laughter erupted from the skeleton’s throat as Sans broke out into an outburst. The laugh rung through the room and out into the connecting hallway; cold, empty, and broken. It tore at his soul and sent waves of pain rushing down his body, but he couldn’t make it stop.

He kept laughing. He couldn’t breathe and his eyes were starting to water, but the laughter kept coming, frail and threatening to break into sobs at any moment. But he couldn’t stop this fit of laughter that had seized his body, becoming completely outside his area of control. Sans didn’t stop when his voice broke and the outburst became nothing more than strangled weeping. Nor did he stop when he began to choke on his own tears.

Here the skeleton was. Lying abandoned on some dirty floor of cracked and smashed tile in a forgotten lab in a distant Underground that wasn’t even in the same universe as his home. He was trapped by some mad scientist who only wanted to experiment on the skeleton with painful tests. And yet only one night ago Sans had been curled up on the couch with his big bro watching some silly movie like they always did. Only one night ago, Sans had instead been trapped by the warm embrace of his brother. He’d been safe and sound in the confines of his own home, where his biggest concern had been making sure he didn’t burn dinner.

Now he was here. In an Underground that seemed to be full of things that Sans couldn’t have dreamed of even in his worst nightmares. In just one day, he’d nearly been raped and killed by an evil version of the monster that Sans had always thought would protect him. He’d nearly been killed by some sort of serial murderer in Waterfall, who had a whole room full of the remains of their past victims. Sans’ skull had been smashed in - the skeleton betrayed by someone who had promised to help him. His own soul had become… _mutilated_ , taken from him unwillingly and molested with needles and Determination. Infused with a substance that could very well cause the skeleton to melt to death.

It was such a sharp contrast that it felt like it was a joke in itself. A miserable, twisted joke. Is that what he was? Sans pulled his legs tight to his chest, curling protectively into a ball and ignoring the pain the motion caused.  _Just make it stop._ Sans begged in his mind, knowing they would only be wasted if he said them aloud. Anyone listening in this universe wouldn’t help him. They didn’t care. _Please. Make it stop._

 _I want to go home._ Even if home was somewhere across time and space, in a completely separate state of being compared to where the skeleton was now. Sans didn’t care about timelines or universes. All he wanted was to go home- to his Underground. To his Snowdin and his Papyrus. Back to a place where things made sense. Back to a place where he was safe.

_Just please… somebody… anybody. Make it stop._

Sans knew no one was coming to save him. His was in a place far beyond the control of his brother and friends. Sans was completely abandoned here. Nobody was coming for him. Nobody in this universe cared for him. Nobody in his own could reach him. Sans was utterly alone.

But that small, foolish part of the skeleton still expected someone- anyone- to walk through the doorway of the room and rescue him from this pit. That some monster would come and save him now. That those he trusted and loved would find their way to him. Maybe his brother, **his** Alphys or even Undyne. Heck, even _this_ universe's Riverman. Who knew? At this point, anyone was better than the twisted evil doctor who had captured him. And anywhere was better than this dark, damp lab Sans was stuck in.

For a full minute Sans lay silently on the ground, waiting- hoping- begging, for someone, for anyone at all, to come save him. To take him away from this place. To take all his pain away and make him feel better. To make the awful torment end.

But as that one minute passed, it remained uneventful. No cross-universe traveling version of his big bro came to save him. No leader of the Royal Guard came to his aid. No Royal Scientist invented something to save him from this awful place. All that happened was Sans continued his painful wheezes, which seemed to be only worsening as time went on.

So Sans waited longer. The battered and beaten skeleton lay motionless on the dirt lab floor for another minute. And then another five. And then-and then...

 _N_ _othing._  Sans kept waiting.

_But nobody came._

* * *

“So if you don’t mind me asking,” Sans began to voice the question that had been lodged in his mind for the past several hours as he had watched the other two monsters work. “How exactly does this whole thing work?”

It was just him and Undyne in the lab again. The larger skeleton had stepped out once again- this time without the Royal Scientist pestering him to do so. All they had left to do was test their new machine and make sure it was functioning accordingly. Apparently, that was a one monster job.

Sans guessed it had taken a number of hours for them to put the final touches on the contraption. Though in reality, it was impossible for the skeleton to guess. Sitting on the floor of the corner of a dark lab doing absolutely nothing made it kinda hard to keep track of time.

“Huh?” Undyne jumped a bit from her spot in front of the metal machine, where she had been examining some of its wiring. She had been so enveloped in her work that she’d completely forgotten the smaller skeleton’s presence in the room. He hadn’t said a single word for _hours._ “What was that?”

Sans bit down hard on his tongue. He shouldn’t have asked. He shouldn’t allow his curiosity to get the better of him like that. While he did _want_ to know how this metal contraption was supposed to send him back to his timeline, he didn’t _need_ to. Asking stupid questions that he didn’t need to know the answer to was something Boss did not appreciate, and Sans didn’t want to get into the habit.

“How’s it work?”  Sans repeated his question anyway. This wasn’t his timeline. There was no Boss to punish him for his curiosity. At least not for now. In an hour or two, when he was back in his Underground… that’d be a different story.

“Oh!”  The Royal Scientist’s eyes lit up bright, and it left Sans wondering for a second if he was going to end up regretting to ask such a question. “I’m so glad you asked!”

Undyne didn’t get to talk about science with many monsters. Her few friends were either completely unfamiliar with the topic, completely disinterested in it, or both. Papyrus being the one exception, but even he didn’t work with her too much. Queen Toriel was more interested talking about other matters that affected the Underground than science, Alphys just laughed it off whenever she tried to explain some of it to her- remarking that it was “awesome!” but still having absolutely no idea how it worked- and the Sans she knew just ended up with his head spinning in circles whenever Undyne brought up topics like it.

So in a way, it was like this other Sans had walked straight into a trap that he hadn’t known was there, because the Royal Scientist was more than happy to explain to laws of timelines and the rules of the multi-verse and any other science topics he wanted to know about.

Undyne completely abandoned her tests with the machine, now favoring the opportunity to go in great length of each part of the machine. “It all starts right here,” Probably a bit too enthusiastically for the small skeleton who visibly flinched as Undyne’s finger flew towards to glass container at the center of the machine.

“Here, we place something strongly connected to Sans’ soul- the Sans’ of this timeline,” Undyne’s fingers trailed down the wire connecting the jar to the control panel. “We can use that connection to pinpoint which other alternative universe Sans is in, and then narrow the scope of this machine so that it only focuses on those two timelines.”

Undyne was staring at the other skeleton wide-eyed, making Sans feel the need to say something. “Okay.” That part made some sense to him.

“We will then attempt to swap aspects of each of those timelines. In the case of this experiment, the aspects we are changing are the Sans…es.” The skeleton’s pair of red eyes followed the scientist’s scaly blue finger as it motioned towards the newest addition to the machine, the large part that the other Papyrus had been working on before.

“This is the part that is responsible for that,” Undyne was glaring at it with a worried expression that Sans didn’t quite understand. “This smaller machine does most of the work. It’s heavily infused with magic,” The Royal Scientist shifted restlessly on her feet. “I usually prefer to avoid depending on so much magic with my machines. Magic and engineering don’t mix well.”

“Why’s that?” Sans couldn’t help but ask yet another question as soon as it popped into his mind.

“Magic is emotional. It comes from a monster’s deepest feelings and desires. It’s powerful, yes, but it’s unreliable. Machines are rational and logical. Their power source is a steady supply of energy.  They are designed to work every time. They’re predictable and follow certain rules and patterns.”

“Oh,” Sans could see how that would be a problem. “Adding something that’s so strongly related to feelings to something that’s just supposed to deal with logic.” The two forces were opposites- trying to make them work together would just end up to them clashing against each other.

“Yep,” Undyne was a bit surprised that the monster was able to grasp the concept so quickly. She had once tried to explain the same concept to Alphys in relation to the special oven she had created for her. It was designed to heat things at extreme temperatures by harnessing the Core's geothermal energy. It still took a little bit to heat up, so Undyne’s best friend had decided to attempt to use fire magic in addition to it, just so she could bake a batch of cookies in under a minute.

Combine that with the fact that Alphys was admittedly _horrendous_ with fire magic, and it was a recipe for disaster. Well, actualy, it was a recipe for cookies, but it still did not end well. Long story short, the day ended with Alphys burning her house down for a _second_ time, and the now temporarily homeless warrior having no choice but to crash at Undyne’s lab for a few days. Funny enough, the cookies had turned out to be pretty good when the two had been eating them together that night on Undyne's couch.

“Of course, involving magic is something we couldn’t very well avoid completely when working with an issue as complicated as the timelines,” Undyne twiddled with her hands idly as she continued her explanation. “Plus, it’s impossible to not cut some corners when working with such tight time constraints.” And cut corners they did. Papyrus and the Royal Scientist had skipped so many of the important steps when working on a machine like this that Undyne was sure even those with a basic understanding of engineering would’ve been appalled.

“So… you’re basically relying on lots of unpredictable magic and luck to pluck your Sans out of one universe and replace me and him?” Sans translated.

“Err… yeah,” _When you put it like that…_ Undyne rubbed the back of her neck awkwardly. It may not have been the best plan, but it was their plan. And Papyrus seemed convinced that it would work. “But there’s more to it than that-”

“How do you know it will work?” Sans interrupted the scientist with the one question that had been attacking her mind with a storm of doubt since the second she had begun working on the machine.  “How can you be sure that all the magic will do exactly what you want it to?”

 _I’m not._ Undyne was tempted to voice her thoughts out loud, but the Royal Scientist was glad she didn’t when she heard the voice of a third monster announce their presence in the room.

“Because it will,” Sans jolted at the sound of the other Papyrus’ voice in the doorway beside him, immediately straightening as was his natural inclination for whenever his Boss checked on him at his post in Snowdin. Even though it wasn’t his brother- just another universe's version of him- the years of survival instincts that had been ingrained into his head were impossible to forget after just one day. Which was good, because it meant Sans could go back to his timeline already well familiar with its rules.

“It’s _going_ to work,” The anger in the larger skeleton’s voice made it seem like Sans’ question had stuck a nerve. His voice seemed deeper than it had just before he had left, even more akin to Boss’ gruff, no-nonsense tone. It was as if he had just went through a full pack of cigarettes – which, judging from the smoky smell of his orange hoodie that Sans’ could make out from where he sat, the larger skeleton very well may have.

 _Someone's anxious._ It hardly took a trained eye to see that. Sans could easy make out the worry in the larger skeleton's eyes, even if they were pointedly shifted away from his direction, instead gazing across the room at Undyne and the machine. The nerve Sans had struck with the other version of Boss had been concern. Concern that this machine might not work after all. The way the larger skeleton responded made it seem like he was trying harder to convince himself than Sans.

“We ready to do this?” Papyrus looked up from the smaller skeleton to Undyne, who had forgotten the testing she was supposed to be doing until that very moment.

“Oh- right!” Undyne jerked back into action, turning to face the machine to perform some last tests to make sure the parts of the machine were running smoothly and would complete their respective tasks. She anxiously checked each aspect of the metal machine, quickly scanning each part as fast as she could so she wouldn’t become the next victim of uptight Papyrus’ quick temper. “Just about!” She assured the skeleton, who relaxed a bit at the update.

“Great,” Papyrus reached to his pocket unconsciously, before the realization struck him that he had no smokes left. The larger skeleton sighed. His last break had done next to nothing to calm his panicked nerves, and Papyrus had even gone through the rest of his pack. He’d have to pick some more up from his stash in the house.

Papyrus walked out from his spot beneath the doorway and moved towards Undyne and the machine. Not much longer now. Just a few more minutes and they’d be doing this thing. Just a little while and he’d have his little bro back with him. The larger skeleton glanced back at the other version of his brother that was sitting in the corner. He did he best to bury the guilt that crawled its way to the surface of his mind as he looked at the other monster.

“Get up,” He told the Sans. The smaller skeleton glared angrily at him, but still rose to his feet.  _Who does he think he is?_ Sans thought bitterly to himself. Just because he was another version of Boss didn’t mean that he was entitled to ordering the smaller skeleton around as well. Just because the other skeleton was bigger and probably stronger than him didn’t mean he could control him as if he was Boss.

 _But it also did._ That’s who Sans always was. Someone to just take orders, to be used. That was his purpose. Seems like this Papyrus had figured that out as well. Sans had his fun- he’d try to act rebellious and tough. He’d try to fight against his Boss as much as he could. But when it came down to it, his Papyrus was the one in complete control of him, and Sans knew better than to ignore a direct command from any incarnation of the skeleton.

Sans edged closer to the device, still behind both Undyne and the other Papyrus. The Royal Scientist had backed away from the contraption- her final look over of its components completed.

“Everything appears to be in order,” Undyne stood right beside Papyrus, leaving a gap between the two monster just wide enough for Sans to see the machine through. “It’s… done.”

The three monsters stood in silence for a moment, taking it all in. It was done. After less than a day of work, and they were finished. What stood before them was the machine that would send Sans away from this Underground that seemed too good to be true back to the hell he had crawled out of.

It wouldn’t win any awards for “Prettiest Design,” that was sure. But then again, it was never supposed to. All it was supposed to do was work. If that was the case, than that was good enough. It didn’t matter that the machine was bulky and awkward. Nor the fact that wires were jutting out of the metal spaces and jamming into other parts of the creation. Yes, it was a completely unorganized mess- that was what happened when two monsters jumped right into building a machine with no prior planning- but that was of no importance.

Sans had to admit. It was unlike anything he had ever seen before. It was even a bit impressive- at least for the duration of time the other monsters had spent on it. In just under a day, they’d constructed a full machine that was supposed to send Sans across the fabrics of space and time. Whether Sans wanted to go back or not… that was a completely separate matter. A different topic that was of no importance to the other two monsters in the room.

Now, it would be even more impressive if it worked.

"We need your soul."

* * *

_Nobody is coming._

Sans was alone. He was trapped. He was going to keep being tested on. He was going to be put through more horrible experimentation.  _And nobody was coming to save him._ Sans could lay motionless on the cold tile floor for as long he wanted. It wouldn’t change the cold hard truth that he had to face this all alone.

 _The cold hard truth._  Sans had never been one for that, huh? The skeleton had grown up in a universe where everything was sugar coated specially for him. The truths he knew were sweetened with lies to make them seem much better than actually were. Sans had no experience with dealing with the rough, hard to swallow facts.

He’d broken down sobbing today more times than he could count. Back in Snowdin, on the boat to Waterfall, at the echo flower, in the lab… gosh, he really was the crybaby, wasn’t he? Crying didn’t solve anything, yet he still did it.

Sans couldn’t handle anything by himself. He’d run off to his big bro and cry for help whenever things got too tough. Sans expected Paps to always be there to solve his problems. To fight his battles for him. But what happened when the larger skeleton was far away- when the distance between the two monsters literally extended to  _universes?_ How could his bro be the one to help him then? How could Sans possibly expect him to?

He was in this alone. No one was coming to pull him out of this dreadful situation for him. There was no one Sans could depend on to save him any longer.

That revelation- Sans knew it would be too much for his fragile, frail, and foolish mind to handle. It seemed like everything was. As soon as the cold hard truth that he was alone- that  **no one**  at all was coming to help him- set in, Sans knew he’d be back to the tears. He’d begin to weep and sob, devolving into nothing more than a worthless sack of bones.

After all, that was his first reaction when things got tough. Cry. Cry and cry and cry until someone else made things all better for him. He couldn’t ever fix anything himself. Only others could do that. But in this universe, nobody cared about his tears. Nobody cared about him. Nobody cared. Which meant Sans was in this completely by himself.

 _I’m alone. I’m alone. I’m so alone._ Sans repeated it in his head. Those strange combinations of words seemed so alien to him. Sans had never truly been alone in his life. He was always surrounded with his great friends. And before he’d met them, he’d always been with his awesome bro. He’d never been alone. He’d never even thought that he could be.

But here he was; alone and abandoned, trapped and tortured. Completely devoid of any hope that anyone was coming to save him, because this Alphys had said it herself. It was nearly impossible to cross across universes. This trans dimensional travel of his own was nothing more than a cosmic anomaly.

He was alone. And being alone was something the small foolish skeleton couldn’t do.

But there were no tears.

Sans couldn’t help but be surprised. He… wasn’t breaking down like he would’ve expected- like he would’ve done any other day of the week. _Where was the sobbing?_ Where were the tears? There were none.  _Why?_

There was... something else. Something else, bubbling to the surface in his soul, crawling out of the pit of despair he had dug himself into.  _I’m alone._ It was true, but the fact weirdly enough didn’t seem to bother him anymore.  _No one is coming to save me._

 _So I’m just going to have to save myself._ Sans had gotten himself into this mess. He’d been stupid and made a couple bad decisions. But his actions had brought him here, and his actions could get him out.

 **Determination.**  That’s what that feeling was- filling the deep holes of Sans’ soul. He was filled with Determination; a will to live and push forward. It wasn’t truly his own, and it may or may not have been slowly killing him from the inside. But neither of those things mattered. All that was important was the warmth spreading through his body. No, not warmth, that wasn’t right. This new feeling wasn’t like the happiness or joy Sans was used to, no, it was something new. Not warmth, not comfort, but just… purpose. Fulfillment.

_I’m not going to die. Not here, not ever._

The latter part of the statement was wrong and the skeleton knew it. He’d die someday, whether he liked it or not. But the adrenaline pumping through his soul was so strong that he could hardly even care. He could get out of this dark lab. He  _would_  get out of this place where he was imprisoned. Sans was determined to do so.

The Determination was just what the small skeleton needed to push forward, to force himself to ignore the gut-wrenching, horrible pain that protested his every movement as he began the long journey to stand up. The newfound feeling resonated deep within his chest, within his soul, numbing the terrible pain he had been experiencing in prolonged torment just a moment before. It still hurt, all of it, but that hurt didn't matter. All that mattered was that Sans got out of here.

He began with nothing more than a slow crawl, clawing along the tile floor, with every inch being a struggle. His bones scraped against the hard floor, the new clothes Sans wore providing little protection to the white bones that made up his body. But a little scraping wasn’t going to stop him, not when he’d already been through so much more in one day.

When the skeleton reached the table, he tried his best to prop himself up on it, using it as a support. It was too bad that he didn’t notice that the table was on wheels until after it slipped out from beneath his grip as he was halfway to standing up.

As the table slid out from Sans’ hands, the skeleton’s body slammed back to the floor hard. He winced at the feeling, but it was hardly enough to stop him. The Determination injection circulating through his soul was so strong that Sans could feel the strength pulsating through his body with every beat of his heart. He’d get out of here. He was sure of it. With so much Determination- with so much pure willpower and strength- there was no way he could fail.

Sans crawled over to the nearest wall, deciding instead to use the immobile object as his support for his second try. Bracing himself against the wall, he tried his best to rise to his feet. Wobbly legs gave way the first time he tried to stand, nearly sending him collapsing back to the floor if he hadn’t been ready to catch himself. When he did finally get his legs underneath him, they felt about as strong as twigs, ready to give way any second without so much as a warning.

 _Hug the wall._  Sans told himself, pressing tight against the one unmoving support he had available to him in the room. He was too weak to walk without it. His first steps were nothing more than a horrible stumble as the skeleton groped blindly through the darkness. He nearly crashed back to the cold floor beneath him on more than one occasion, and he did end up doing so more than once. Each time though, he found that same strength pounding in his soul, demanding that he keep moving forward. That he escape from this awful place.

It was a slow process. Each step nearly ended in turmoil. Each few feet was an uphill battle the whole way through. It took Sans a minute to clear the same length he could usually clear in seconds. But somehow he still managed to find his way out of the room he had found himself trapped in.

 _Keep going._  Sans told himself as he emerged from the confines of the dark room into a just as poorly lit hallway.  _There’s got to be an exit somewhere._  The skeleton had gotten down here somehow, and he'd escape that same way.

The skeleton had no plan whatsoever. He didn’t have the slightest idea where he’d go after he escaped the lab. He was too weak to cross back to Snowdin, and even if he could make his way back to the snowy town, there was nothing there for him. Nothing but a killer that would have no trouble finishing him off now that he was in a sad state like this. No, Sans couldn't go back there... but the skeleton also didn't know how he’d get back to his own universe.

 _None of that matters. Not now._ Sans' first step needed to be getting out of the immediate danger he was in now. His plan for action could wait for later, once he made sure that there would be a later for him.  _There **will** be a later._ Sans was sure of it. As long as he found his way out from these of dark and narrow corridors, he’d find safety. Somewhere. The specifics weren't important.

The skeleton swung his head down to each of the ends of the hall, scanning his new surroundings. The hall seemed to branch off in separate directions at each side, meaning that Sans was stuck with just one important decision to make.

_Which way to go...?_

* * *

_We need your soul._ The larger skeleton said the words as if they were meaningless, like they were something as trivial as a simple hello. His calm and steady voice was a stark contrast to the statement- almost as if the other monster didn’t hear just how crazy he sounded.

"Excuse me?" Sans found it impossible to believe he had heard the other monster correctly. Yet sure enough, a thin bony hand hovered expectantly before the smaller skeleton, extending from the other version of Boss who waited patiently for the item he demanded from Sans.

“Your soul,” Papyrus repeated his request, glancing away from the machine in front of them back to his left at the other monster. “We need it."

A direct order like that was something Sans would've followed with blind obedience in any other situation. Yet this certainly wasn't like "any other situation." This other version of Boss was asking for Sans' soul- no, expecting it from him- and there was no way in hell Sans was stupid enough to hand it over.

A monster's soul was the most important thing a monster possessed. The entirety of a monster’s being- their feelings, their thoughts, emotions; all of it- came from their soul. It wasn’t only the thing keeping a monster alive and breathing, no, it was the very culmination of themselves. A monster soul was quite literally _them_. It was the most fragile and sensitive part of any monster. Which also meant it was their weakest point. A direct blow to the soul of even the strongest monsters might just be enough to dust them completely.

If one monster were to gain control of another’s… they would have complete control over them. Utter dominance. Their life would be in that monster’s hands. Their will could be bent and broken to the desire of their new monster. With a monster’s soul in hand, you were their _god._ You controlled whether they lived or died. You controlled everything about them. You controlled them. You _owned_ them.

 _Being owned._ Sans knew exactly what that awful feeling felt like. It wasn't something he was particularly fond of. The feeling of knowing that other monsters saw you as their lesser- as nothing at all, someone that was too weak to protect themselves. So weak that you weren't even considered a monster, instead only the property of someone else- someone who owned and used you.

The feeling of being so pathetic that other monsters knew they could walk all over you- could squash you beneath their feet and treat you like dirt, because you weren't their equals. The feeling of hardly being able to blame them for doing so, because it was your fault that you were in that position in the first. Because you were too weak to fend for yourself.

The feeling that Sans woke up to everyday. That he experienced every time he walked into Grillby's or into Boss' house. The feeling that made him feel so exposed, so out to the open for anyone to prey on him. The feeling he felt every time he remembered the collar tied a little too tight to his neck.

It was a shitty feeling. And there was no way in hell that he’d ever willing make himself feel that way again. He didn't ever want to let himself be put in another situation like that again- no matter how nice and kind these monsters may have seemed. He already had one owner. He’d much rather be dead than have another.

"No," It was blatant disobedience, not just him being rebellious for the sake of being difficult. Sans had clearly gone against a direct order, and the words felt strange coming from his mouth. It was hard to believe he had said them. "You're not getting my soul." The smaller skeleton fought against the instinctive urge to flinch and hide away from the larger monster, trying his best to hide the fear he was feeling.

"You're not touching my soul," Sans repeated the words again. He wouldn't let them take his soul. He wouldn't let anyone take his soul. He took a step away from the other two monsters, beginning to put some distance between them all.

"Papyrus?" Undyne turned towards the larger skeleton, with a look of confusion on her face. "What are you talking about?" They'd never discussed this. "This was never a part of the plan."

"His soul," Papyrus didn't take his gaze off from the other version of his brother as he began explaining. "We can use it to find the location of our Sans."

The Royal Scientist glanced away from the two skeletons back at the machine's empty glass container. "You want to use his soul?!" She nearly choked in disbelief on the words. "That's crazy!"

"Is it?" Both Papyrus looked at Undyne only for a moment. "What would have a stronger connection with our Sans' soul than another version of it?" 

"I..." Undyne faltered for a moment, realizing what Papyrus meant. "That's not the point here! You're not thinking straight, we have other options-"

"But this is our  _bes_ _t_ option. We need to save our Sans _now,_ " Papyrus looked back at the other universe's version of Sans. The smaller skeleton was still backing away, nearly pressed into the corner of the room now. "His soul is the best choice we have."

"Papyrus-" The larger skeleton only shrugged off the scientist's hands as she tried to stop him as he took his first step forward towards the other skeleton.

 _Oh shit._ To say Sans was panicking was an understatement. His soul was beating impossibly fast in his chest. A small part of him was aware of the fact that he should teleport out of here. That same part of him was drowned out with panic and fear that fueled the terror which paralyzed his mind from thinking straight. "Stay away from me- or else!" He tried to make a threat, but he sounded so weak and pathetic even to himself.

His scared warning had no effect on the larger skeleton either. Sans could feel his spine slam up against the wall behind him and another wave of terror took him over. He was out of space to go, yet the other version of Boss was still making his way over to him. His large strides cleared the distance between the two monster faster than Sans would have preferred, and each step he took closer to him, more fear came over the smaller monster.

Sans hated being so scared. Hated being so worthlessly pathetic and useless. Hated that he was so incapable of defending himself that he just curled up in a ball and hoped that the pain would go away whenever he was in danger that was just too much for him.

 _Why?_ Sans' hands scrambled blindly against the wall behind him, searching for something- anything- to help him.  _Why am I so scared?_ Why couldn't he ever just get a hold of himself?! Why did it always feel like he was fighting against himself in situations like this? A part of him wanted to cry, and another wanted to stand and fight.

He could be strong if he wanted to. Sans knew that he was more than capable of fighting. He may not have been able to do it well- but he  _could_ fight. He was sure he could beat off any pathetic whelp from this universe. Here it seemed like fighting was something the monsters weren't very familiar with. Sans could protect himself from them. So why was he afraid? So why was his body trembling in fear- and his eyes beginning to sting with the first signs of tears forming?

"Can you _please_  just give us your soul?" It was almost as if the larger monster was begging Sans. Like he was still sticking to that damn "kind and nice" shtick that Sans could see right through now. "We really could use it."

Sans could see it clearly now. The kindness and niceness of this whole universe- it was nothing but fake. Even the idea of it all was too good to be true. A world just like Sans' own, where everybody treated each other with respect? Where monsters didn't die everyday? Where the weak weren't preyed on and looked at as lesser? It had always been an impossible dream that Sans had held secretly to himself. And it was just that- impossible.

Monsters weren't nice. They weren't kind. Nobody was. The world didn't work like they. No world did. Because monsters- humans- everyone, were selfish and did things only for themselves. The only person anyone cared about in the very end, when all was said and done, was themselves. Everyone only did the things they would benefit from. Actions that only they stood to gain something from. Sans knew that. He knew all about it.

So why was it he had forgotten that one simple rule when he had arrived in this place? Why did he take it for granted that the monsters here were all kind and happy and selfless? A world like that- a world so perfect that it broke the rules of Sans' reality- didn't exist. They were just a fairy tale. A dumb old dream. The monsters of this place only pretended. The seemingly nice monsters and their friendships and feelings of concern for one another- all of it. Pretend. Fake. Just a cover up for what the monsters really were- for what everyone really was. Selfish, self-centered, and terrible. Twisted and evil bastards. There was no good. Because the good didn't survive. The good was already gone. Dead. Because good was a weakness. And those with that weakness had no chance fighting for their lives.

"We're not going to hurt you," The larger skeleton promised. He was standing just a foot away from the other skeleton, who remained pinned against the wall breathing heavily. "I just- we just want to save our Sans."

 _"Bullshit,"_ Sans spat the word back with feelings of only anger. He wasn't stupid. He knew exactly what would happen if he gave them his soul. He knew that the other monster's promise was just some poor lie to make Sans feel safer. He wasn't going to fall for it. He wasn't going to let himself be controlled.

The question was, did it really matter what he did? Boss- any version of him- wouldn't care what Sans wanted. If Sans failed to follow his orders, than he would simply take take what he desired.

"St- stay away!" It was more of a plead for help than a threat as the skeleton flattened his back against the wall behind him. Sans was too scared to gather magic to defend himself through any form of attack. All the smaller monster could do was pull the ends of his jacket tight over his chest, protectively hugging it over his red turtleneck the covered his soul.

Something wet slipped from the inside of Sans' eye sockets, falling down the cheek of his skull and hitting the ground below him. In the dark shadows of the underground lab, the red drop of liquid went unnoticed by the larger skeleton.

 _Dammit._ He was crying. Sans closed his eyes tight, in an attempt to hold the tears back. He was crying now, of all times. His soul was leaping in his chest and his mind was gripped by nothing but panic and fear. Another monster was about to take his soul from his chest and use it to bend him to his will. And all he could do was cry and show them just how worthless he really was.

He was so damn weak.

 _"Please,"_ It was Sans' turn to beg. He doubted the plead would stop anyone, but he was just desperate enough that he had to try. "Don't..." His frail voice trailed off, finally breaking and shattering. A large hand landed on Sans' shoulder, and teary red eyes shot open.

For a quick second, the monster Sans' was looking at wasn't some orange hoodie clothed version of his Boss. No, as Sans' wild eyes shot open wide in panic and terror, the skeleton looking back at him was one that was much more familiar to him.

Orange cloth faded into black spiked armor. The hood melted into a familiar red scarf, battered and torn. White eyes turned instead to a glowing red that matched Sans' own. Where flat teeth had been seconds before, shard intimidating fangs stood. A long scar ran down the skeleton's let eye as he glared into the depths of the smaller skeleton.

The skeleton opened their mouth, but the words that came out were something that Sans had heard repeated all too often before. Not only in his worst night terrors, but in real life, too.

 _""If you won't give me what I want..."_  The lax grip on Sans' shoulder tightened until it was bruising the bone beneath the skeleton's jacket. Five bony fingers, clawed and sharp, dug into the bone, threatening to break it under bare hands. "Then _I'll simply take what I desire."_

"No!" Sans screamed as the panic that had been building up in his system burst out. The skeleton pulled away from out of the larger skeleton's grasp, struggling to get free. Tears flew from his eyes, scattering across the tile floor beneath him. "Stop!"

The hand that had been on shoulder was quickly removed, and suddenly Boss was gone. In his place was instead the same skeleton Sans had woken up on the couch that morning. His two hands were being held up in a manner of surrender as he retreated away from the scared small skeleton. It was confusion and not anger that filled his eyes, and his desire to take Sans' soul seemed to be gone.  _Or maybe it had never been there in the first place._ The defensive look on the other Papyrus' face made Sans wonder if the other skeleton ever really had any intent to forcefully make him give up his soul.

"Stop Papyrus!" The Royal Scientist finally broke into action, having previously been frozen uncertain across the room from the two skeletons. She grabbed the larger skeleton by the shoulder and pulled him away- something that was more than unnecessary, seeing as how he had already backed away from the smaller skeleton.

"I... jeez," Papyrus could feel even more guilt already beginning to crawl down his spine. It had been one thing to ignore the chipping on the other Sans' arm... but this was a completely different matter. The other version of his brother was in tears, hyperventilating and panicked, while pressing himself tightly to the wall and keeping himself as far away from Papyrus as he could. And it was Papyrus' fault.

The larger skeleton had been so focused on saving his younger brother that he hadn't been paying attention to his actions with _this_ version of him. Papyrus had said they needed the other Sans' soul. He'd cornered him into the end of the small room, leaving him nowhere to go.  _He didn't think I would-_ The realization froze the larger monster in his tracks.

 _Oh shit._ Here he was, demanding the other monster's soul. When all the other monster had ever known was hurt and pain and abuse. Here the larger skeleton was- another version of the Sans' main abuser, asking for him to hand over the most sensitive part of himself. It wasn't hard to put two and two together and figure out what the other skeleton had assumed.

"I didn't mean to- I wasn't..." Papyrus trailed off as he looked back at the smaller skeleton. Absolute heartbreak was the only way he could describe the feeling he experienced as he saw the smaller skeleton huddled on the floor, in a sobbing mess.

 _He looks just like Sans._  Like _his_ Sans. Whenever his bro had one of his bad dreams... or whenever he broke down into tears. The differences between the two of them were there, but so were the similarities. Red tears flew to the ground as opposed to blue ones, as the skeleton clutched himself tight just like his brother did. Quick short breaths as the skeleton did his best to get a hold of himself.

Yet while his Sans actively reached out for help and comfort from the larger skeleton, this monster rejected it. Not because of some stupid tough and macho thing... but because of actual fear. That look in the Sans' eyes as he shifted closer to the wall behind him, wanting to put even one more inch between himself and the other monsters in the room was one of pure terror. 

 _He's afraid of... us._ No. That wasn't quite right and Papyrus knew it.  _He'd afraid of me._

 _He thinks I'm like his Papyrus._ His messed up, abusive version of the skeleton. The one who clearly didn't treat this Sans right. _I've given him no reason to think that I'm not like him, either._

This monster was his brother. Different timeline or no, Sans was still Sans. There were no words Papyrus could use to describe the guilt he was feeling. Nothing he could say would make up for how he'd treated this version of his brother like dirt for the past few hours. Because he'd come from a timeline where he was treated poorly, Papyrus had thought it was okay for him to do the same. He had thought he had to completely ignore this version of his bro because his own was in danger somewhere. 

_I'm... I'm a terrible person. Just like his Papyrus._

"Papyrus?" Undyne felt awkward suggesting this, but she knew it was what needed to be done. "Maybe you should... leave." It was obvious the larger skeleton was the reason behind the other Sans' state. It would be easier to calm the smaller skeleton up if he weren't there.

"I-" Papyrus began to protest, but he could feel the words die in the back of his throat as he looked at the curled up and sobbing skeleton. The other Sans' red eyes remained trained on the same floor he sat on as red tears fell from them. The sight was too much for the larger skeleton to handle. "Yeah... right." Undyne was right. It would be best if he left for a little while. "I'll... uh... try to find something else to use for the machine."

"You do that," Undyne's voice made it clear that she hardly seemed to care about that right now. Papyrus took one look at the smaller skeleton before tearing his gaze away from him, the guilt too much for him. Without another word, he ported out of the room, leaving one Royal Scientist alone with a clearly upset monster that she had the sole responsibility of cheering up.

Undyne wasn't so good with monsters. She was much better with machines. With machines, everything made sense. Things worked when they were supposed to. Computers were programmed to perform their tasks, and machines were designed the same way. When one of those things broke down or failed to work, it was a simple fix- a small error in the coding or in-consistence in the design. To solve those errors, all one had to do was find their way go inside and fix the mistake.

With monsters, it was a different matter completely. Monsters didn't make  _sense._  Everything about them wasn't so simple and easy to understand like with a machine. Monsters were complicated. Feelings and emotions were harder to make sense of then coding loops and electricity. With a monster, there were too many things to take into account that they were impossible to work with.

"You're not getting my soul," Undyne turned back to the skeleton hunched in the corner.

"That's- that's fine," The Royal Scientist hadn't never even thought about using the skeleton's soul in the machine. She would never ask that of him. Undyne figured it must've been hard enough to trust a bunch of cross universal lookalikes without them asking for something so personal. "We can use something else for the machine."

"Okay," Sans could feel the panic in his soul beginning to still, and the newfound relief sweeping over him.  _Fuck._ It been awhile since Sans had an attack like that. Sure, it was a minor one- but Sans had secretly been hoping that he was done with those. The skeleton really wanted to stop being so weak and pathetic, to stop breaking down into a sobbing mess all the damn time.

"Do... do you mind if I ask what that was?"

"I do actually," The skeleton bit the words back a bit too quickly, making it pretty clear that he wasn't too eager to share his experience with the other monster.

"Right..." The two monsters returned to silence as Sans took long steady breaths to calm his nerves. Undyne bounced nervously on her feet, knowing she should probably say something to reassure the skeleton, even if he didn't want her to.

The skeleton froze up for a moment as the scientist began to move, but it only took a moment for Sans to figure out she was just sitting down on the floor beside him. "Listen," Undyne's ignored the feeling that she should probably just keep her mouth shut to avoid the chance of making everything worse. "I know that things may be... different, to say the least, in your timeline..." That was the understatement of the century. "But here, we don't... _hurt_ each other like that. Papyrus... he- he never would've taken your soul from you if you hadn't wanted him to."

Sans knew that the scientist was being honest. Despite all his beliefs and previous ideas, he had seen the Snowdin of this universe. He'd seen it's residents, and witnessed their kindness and compassion for one another. He'd witnessed the caring this Papyrus had for his brother. Without the panic in fear clouding his mind, Sans could clearly see that was the truth. It was a strange and foreign truth, unlike anything Sans had imagined before. An Underground, _truly_ without the abuse and torment Sans knew. It was a nice idea. It was probably something Sans could get used to, given the chance.

Undyne managed her most comforting smile for the other monster. "It may not seem like it to you but... you can trust us! I promise!"

Something about this dorky, science nerd saying it to Sans made the skeleton want to believe her. He really did feel like he could trust these monsters... even if he had only met them today, they had treated him better than anyone in his own universe. They hadn't abused him. They hadn't attacked him or used him.

"You're safe here!" The Royal Scientist added, bright yellow eyes glowing behind the lenses of her over sized glasses.

 _Safe._  A bit difficult of a concept to grasp for the skeleton. Safety was the thing Sans had been fighting for his entire life- not just for himself, but for Boss as well. Before Sans saw him as Boss, when he was just Papyrus, a little kid, when he was just Sans' brother. Back when Papyrus saw him as more than a pet. Back when all Sans had always wanted safety for the two of them. When all he had wanted was for his little brother to be safe.

"I'm safe here?" The words just didn't seem to flow right out of the skeleton's mouth.

"Ye- yeah!" Undyne kept smiling brightly- a warm, cheeky smile. It was meant to reassure the skeleton... but to Sans, it just came off as fake.

"So what about when I go back to my timeline?" The scientist's happy smile fell as she saw the look of sadness on the skeleton's face and the meaning behind his words sunk in.

"I..." She had no idea to respond, but Sans already knew the answer to his own question.

"I won't be safe. It'll just be back to normal. Everything," This adventure had been a nice change of pace, but it didn't change anything. When Sans got back to his timeline, his welcome home wouldn't be hugs and kisses. It wouldn't be what this timeline's Sans got to experience. No, when Sans returned, all he'd get would be a beating to the edge of his death. He'd be left with bones broken, smashed and shattered, teetering on the line of death and life. Maybe he would die. Maybe he'd get to live just to suffer through more pain.

"I'll never be safe." Sans blinked away the water gathering in his eye, another drop of red liquid falling to the ground. He could pretend all he wanted- the pet and master relationship he had with Boss provided him protection, yet that was hardly the same as being safe. Not like in this universe. Not a safety where Sans got to be happy.


	10. Chapter 10

**Summary for the Chapter:**

> Underswap Sans sees a new side of himself that he never has witnessed before as he tries to find his way out of Dr. Alphys' lab.
> 
> At the same time, Underswap Papyrus and Undyne discuss a plan of action, giving Underfell Sans some alone time to think.

**Notes for the Chapter:**

> Okay, first of all, I just want to thank everyone who's been commenting on any of the previous chapters. It's been an absolute blast to see how much everyone's enjoying this fic, myself included!
> 
> Secondly, I want to apologize for the giant gaps between updates. I'd hate to slip into a tradition where these month long waits between updates become normal, yet sometimes real life gets in the way and things get busy!
> 
> Nonetheless, here we go! I hope everyone enjoys chapter 10, and please, don't be afraid to comment!

Finding the exit out of this awful place definitely didn't turn out to be the easiest thing in the world. Nor did it help that Sans was stumbling through the dark corridors on wobbly legs that felt just about ready to collapse at every given moment.

Each step that the skeleton took fell unnaturally, his body groaning in protest with everything movement he made. All his limbs and bones cried out in one unified calling, begging for Sans to stop- to just sit down and take a break, whether it be for minutes or hours. Yet that wasn't an option. Sans had no clue how long it would be before Alphys realized he was gone. He could only hope that she had yet to do so.

Sans' footsteps echoed loudly through the halls, giving his position in the lab away as clearly as a beacon. With each footfall, bare white bones met the cool navy blue tile beneath him, lining the floors of the corridors; cracked and dirty. His socks and boots had been stripped from him when he had first woken up in this lab, living nothing to pad the bones of his feet from scraping against it. Which meant that each passing step, the sound could be heard down to the ends of each hall, clear and concise.

 _Hopefully she's not around to hear it._  Sans had yet to hear the clicking of the lizard's own feet. At least if his footsteps were giving him away, the same would be true about the mad scientist's.  _Maybe she's just left me forgotten down here for a little while, and gone back up to the top floor of the lab to do something else._  Something else being whatever evil doctors did while bored.  _Probably drown small defenseless animals or something._

Sans footsteps weren't the only noise the skeleton was making. It seemed like Sans' body wanted to make sure that if Dr. Alphys was still down here, it did whatever was in its power to attract her attention to him. He seemed unable to calm the ragged panting of his that seemed to tear through the silence of the underground lab like a knife. The tempo of his panicked wheezes was matched only by the speed of the beating, Determination-filled soul in his chest.

It seemed even Determination wasn't enough to make the panic go away. Sure, the adrenaline from the substance, flowing through the veins of his soul, was more than enough to give Sans the push forward, but it only took away a small fraction of the paralyzing fear and worry that the skeleton was feeling. It wasn't his phobia of the dark that made him feel like that, either. In his current situation, Sans knew such childish fears were unimportant. Something like what lay in the unknowns of the blackness of each hallway was hardly as terrifying as the thought of what would happen if he  _didn't_  get out of this place, and if Alphys found him first.

Sans was terrified of not finding the exit. Scared of what might happen to him if the scientist found him in one of these dark corridors. The skeleton knew he was in no position to run. He could barely even walk without the support of the walls he had to lean on. He certainly couldn't fight. He'd already established that in this universe, his one decent attack provided little to no help. Not when every monster seemed to be such strong, cold, killing machines that a few HP shaved off the tops of their health bars meant nothing.

Which left Sans with... absolutely nothing. He had no options to turn to if the Royal Scientist caught him. When neither fight nor flight worked, there was no third choice to fall back on. Except for being caught and tortured once more. That left the skeleton with just one real, viable option. Don't get caught. The sooner he could make his way out of here, the better.

Yet it wasn't so easy to find the exit- not when the lab was so enormous. The place was a huge, sprawling mess of interconnecting halls and rooms. There were no convenient directories that could help the skeleton make sense of the seemingly unorganized layout of the place, leaving Sans to stumble around blindly, crossing hallways, meeting dead ends, and backtracking to check each part of the place.

And the whole place just seemed... ancient. It felt like no one had seen it fit to maintain or update the place in years. The walls of each corridor were chipped, paint flaking off as Sans' body scratched against it. The lights that lined the ceiling provided no light to the passageways, seemingly burned out long ago- that, or their source of power was cut off completely.

 _I wonder why this place is in such disuse._ Sans' mind couldn't help but find it odd that a big lab like this one would be abandoned.  _Why even build something like this if it wouldn't be used fully?_  It all seemed so impractical.

The skeleton paused at an intersection between two halls, sighing in exhaustion. His whole self ached, and he still had who knew how long to go.  _Focus Sans._  He didn't have time to start wondering about this place. Sure, he couldn't stop himself from being curious, but he didn't have time to waste on something like that. Not when he might not even have enough of that one precious resource to get out of this place.

 _Survive first. Think later._ Sans pushed thoughts about the lab and its abandonment out of his mind and began to focus on the problem that lay before him.He didn't have the luxury of allowing himself to be distracted. Not when one bad decision could mean escape and capture. The skeleton needed to make sure he didn't get lost in this labyrinthine lab. It would be too easy to lose track of where he was going when every hall and turn looked the exact same as the previous one.

The skeleton gazed down each of the three corridors he could go. It was just as he had come to expect. Each way was exactly alike to the others, a nearly pitch black hall, with dust covered doors lining the walls of each side. There was literally no difference between them at all, besides the direction they stretched down.

 _Right it is._  Sans decided after a momentary break, turning the corner into to the new hallway. If his choice just turned out to be a dead end, he'd just turn back and take another right and go down the second path instead. And if that was a dead end, he'd take another right down the third path. That way, he wouldn't accidentally turn back the way he came.

 _I'll find the exit._  Sans was sure he would. The corridors of this lab could only go on for so long. He'd find the exit eventually, as long as he kept looking.  _I've just got to trust myself._

His trekked down the hall, stumbling against the left wall. Sans' shoulder grazed against the doors as he passed by them. The skeleton knew they were more than likely all locked. He'd already tried the ones in the first few halls he'd gone through, and each of them had proved to be inaccessible.

 _So many rooms..._  Despite his best efforts to stay focused, Sans wasn't a monster to ignore his natural curiosity.  _This place really is huge._  Assuming that each door lead to just one room, that meant there had to be at least a hundred rooms down here.  _What could she possible hold in all these rooms?_  Were they all filled with other monsters the scientist had imprisoned and tortured? Were they where the other victims of the Royal Scientist's "testing" were held? Or were they empty?

 _No._ All these rooms couldn't possibly be filled with other monsters like him.  _I can't imagine anyone lasting very long in a place like this._ Especially if they were forced to go through the same sort of testing he had been through in only his few hours here.  _I wouldn't be surprised if they were all empty._

 _Poor things._  Sans' mind strayed to the thought of the other monsters that had to go through he was currently. A wave of despair and sadness swept over him at the very idea.  _Who knew how many monsters had died at the hands of this merciless scientist? Who was to say how many more would?_

This entire universe was just so... so very messed up. Monsters killed one another brutally, like savages. The Papyrus of this place would have no problem raping the skeleton he thought was his brother. Whatever monster that resided in Waterfall kept a graveyard of the remains of their victims. The Royal Scientist  _freaking_  melted monsters by overloading their souls with stuff that was only supposed to be in human souls.

None of his was right. None of this stuff was supposed to happen- not in his universe, not in any. This was the stuff of nightmares, not of real life. It was all so wrong. So… evil. So immoral.

Sans couldn't believe that any monster would do such terrible things to one another as he had seen in this universe. He couldn't believe  _anyone_  would allow that. How could the Queen of this Underground be okay with this stuff? How come this universe’s Royal Guard did nothing to stop such abhorrent crimes? Was everything about this place corrupt? Was everything so wrong?

 _I'm the lucky one._  That realization  probably stung the worst, because Sans knew it was true. Even with all the horrible, unspeakable acts that he'd experienced today, those had still all been in just one day. Sans hadn't grown up in this awful place. He didn't live here. Monsters from this universe lived with these things their entire life. For them... experiences like Sans were the norm.

 _Even here, trapped in this lab, right now._  Sans was still luckier than most. For all the skeleton knew, he may have been the one monster that had the opportunity to get out of here. To escape with his life still intact, to live another day. Sans at least had the shot at that. That was probably more than the other victims of Dr. Alphys could've even hoped for.

All because "he was special." All because of his apparently artificial soul that he still had yet to completely wrap his head around and the injection of Determination that allowed him to find the previously missing strength that he had lacked even to stand. 

 ** _I'm_** _the lucky one._ It took a moment for it to completely sink that Sans had thought what he had. If someone had told him yesterday that he'd be considering himself lucky after popping up in a random universe where he was tortured, nearly raped, actually killed, and then brought back to life, Sans wouldn't just have thought they were insane, he would have been completely unable to imagine any of those things happening to him. 

 _Always the optimist._ That was something Papy had always teased him about. His big bro thought that Sans could see the best of any situation. Even this.  _Guess he was right._

 _I'll find my way out of this place. Then, out of this universe._ The skeleton didn't know how. At least, not yet. Sans didn't even know where to start, but he knew that he'd make his way home. Somehow. He just had to.

 _I'm the lucky one. I’m going to find my way out of here. I’ll get to safety. I won’t waste this chance at freedom._  Sans promised.  _I'll find the exit soon enough._  These dusty narrow corridors could only stretch onward for so long. Eventually, they'd reach their end point. Which meant that eventually, Sans' staggered steps would bring him to the exit. He just had to keep going. He just had to keep on moving.

So the small, injured skeleton just kept going.

* * *

Sans hated himself.

That wasn't exactly a new, earth-shattering revelation. It was something the skeleton had long since discovered about himself. It hadn't been now, sitting alone on the floor of some dark laboratory in a universe that wasn't his own that he had finally made the realization. Sans had always known just how much he'd hated himself. He'd always accepted that fact.

Sans hated the very idea of himself. Hated that he could live with himself, knowing that the only reason he had a life at all was because he had given it up to someone else and let himself become what he had. The skeleton hated that he was just okay with that. That he just accepted that.

The skeleton hated the fact that he was so weak. That he was such a measly, pathetic, scrawny monster that served no real purpose. He hated that his entire existence was meaningless to everyone. That it would make no difference to anyone if he disappeared forever.

He hated that he curled up and cried and the slightest sign of confrontation. Hated that he was still in the position as he had been a half hour ago when he'd broken down with another hallucination. He hated when he couldn't keep those in check. He hated when he couldn't keep himself in check.

He hated himself.

But Sans hated a lot of things.

The skeleton hated the way monsters in his universe would snicker and point at him, not caring whether he saw or not. Sans despised the fact that they all knew exactly what he was. He was disgusted with how each and every one of them saw him as such a lesser that they barely considered him a monster at all. Not that they were completely wrong.

Sans hated the nights when Boss came home drunk. Those nights when the larger skeleton was especially violent. When their usual acts of stress relief and sexual payment turned more from merciless fucking to careless beatings and rape.

He detested the way Boss made him wear a collar, as if his life wasn't already so much like one giant joke. The skeleton hated the way that Boss controlled him- that he owned him. He hated that everything was so set in stone. That being a pet was his place in life and nothing could ever change that.

Sans loathed the tiny little things the larger skeleton did to make him seem less and less like a monster. To seem more like a tamed pet than his brother. Sans was repelled by the idea that he had somehow allowed all that, and that he had done a fair majority of it all without protest, because he was familiar with what the alternative option was.

But above all? Sans hated the way he couldn't bring himself to hate Boss himself.

No matter what he did. No matter how the larger monster treated him. No matter how much embarrassment he was forced to suffer. No matter how much abuse. No matter how many beatings. No matter how much of it all, Sans just couldn't do it. He couldn't hate his brother.

Because in all honesty? Sans loved his brother way too much too ever hate him.

Every time he looked at the larger skeleton, there was still that small part of Sans' mind that could remember when he had been younger. When Boss had been Papyrus instead of his captain and master. When things had been simpler... when it had all been better.

And sure, that had all been years ago, but it was impossible for the skeleton to forget. Sans could still recall the small skeleton he could give piggyback rides to through the snowy forests of Snowdin, or raid garbage cans with in the Captial. He could still see that sparkling, shining smile that had been so goddamn adorable that it almost made him cry every time he saw it. The same smile that Sans had promised to do whatever he had to so he could keep seeing it, every day of his life. Those tiny, beady eyes that gazed up at the other monster's "big bro," with an expression that Sans would've wished to keep on the smaller skeleton's face forever.

No matter how many times his life was brought to its very edge by that same monster, who had grown into the violent murderer and captain of the Royal Guard that he was, Sans couldn't let go of those fond memories of the better times. He just couldn't hate the larger skeleton for the things he did. He couldn't truly harbor any ill intent against the little skeleton he had raised. Raised into what he was now. And maybe things had turned out the way they did because Sans was such an absolute failure that he couldn't do something as simple as keeping his little bro safe from the cruel intentions of the Underground.

Sans couldn't hate the Boss. No matter how hard he tried. So instead... every feeling of anger that came from each night of painful, restless wheezing… came back to the skeleton hating himself. Because he was the one to blame for how everything had turned out. And because it was just so much simpler to hate himself than it was to ever hate Boss.

"Because we should be!" The sound of yelling in the hall behind him pulled Sans out of his thoughts. The Royal Scientist and Boss of this universe were arguing loudly in the other room, attempting to do their best to use constrained whispers to keep their conversation out of the ears of the other skeleton. "And frankly, I don't see how you aren't!" Clearly, it wasn’t working.

 _It's almost like they think I can't hear them,_ Sans thought to himself. For a couple of scientists, they sure lacked common sense. Sans may have been a pathetic, weeping mess, but he could still hear them, especially when the doorway between the two rooms didn't even have a door to block the entryway.

 _Don't they know it's rude to talk about someone behind their back?_ It was clear they were talking about him. And with their hushed tones and whispered words, their debate was still just loud enough that the skeleton could make sense of most of it, Sans didn't get why they even bothered trying to be secretive about it.

Each of the monsters' voices were filled with concern. Concern for him. Was he that much of a joke that pity was all got from these monsters? Pity from the monsters who looked down at him as weaker, as being unable to control his emotions, his memories, or himself?

It was a relative new idea- pity. There was certainly none of that where he was from. But Sans was starting to discover that he hated that too. Especially when he did nothing to deserve their concern.

But that was just how this place- how this universe- seemed to work. The monsters here were capable of more than just hate and distrust for one another. The feelings that drove them were more than just primal urges of lust and anger. The monsters here were driven by compassion and loyalty. These monsters cared. Or they at least pretended to.

Sans had just shown up here in the early hours of this morning, and two of the monsters he'd only just met seemed to care about him enough to show concern for him. Because that was how the monsters of this Underground were. They weren't heartless beasts and murderers. They were much more complicated than that.

Sans had met these monsters less than a day ago, and in that time, he had exchanged less than a handful of conversations with them. He had done nothing to help them, and in fact- his very presence was a problem for them. Yet still, they cared for him more than any other monster Sans had known in his life. And the thing was, they did it for simply no reason.

 _I want to go home._  Sans knew that was only partially true. At least the things in his universe made sense, from a logical perspective. In the Underground he was familiar with, it was every monster for themselves. Kill or be killed or get caught up somewhere in the middle, living a life hardly worth living. In that Underground, Sans understood that he would be treated exactly how he expected. Just as well as he deserved. There, the brutal selfishness of monster-kind was out there in the open for all to see, and it made perfect sense. It was so much simpler. So much easier.

Or at least, it was for Sans. Because there, Sans at least knew his place. He at least fit in a little bit. But in this universe, he stuck out like the stranger he was. He didn't fit in here. He never could. Nor would he get the chance to. 

 _Nothing makes sense here._  The kindness... the niceness. It was genuine. Real, honest, good behavior. And Sans just couldn't get it. Couldn't get the fact that monsters would care for one another like they did here. That they would put themselves in danger by opening themselves up to others. Why would they protect one another, or even a complete stranger like himself? What was his use to them? What was his purpose? Why did they care? They didn't want his soul... and as far as Sans could tell, they didn't want _anything_  from him. So why care?

 _They don't._  The small part in the back of Sans’ mind knew the suspicion was true. They couldn't possibly care about him, not when he was useless to them. Sans did his best to shut out the not so quiet whispers being shared on the other side of the wall he was curled up against.  _They just want to get rid of you. Like everyone else._

Boss had probably been glad when he had awoken to find Sans gone. He had probably assumed that his filthy pet had finally run off. That the nuisance, the thorn that had been in his side for years, impairing and hindering him, was finally gone. Maybe the Boss had even smiled, happy that the one day he had been looking forward to for years had finally occurred. It was even likely that he threw a goddamn goodbye party for Sans, just to celebrate his disappearance. Maybe he’d even invited all of the Royal Guard. Boss had never been popular among the other monsters of the Guard, but Sans imagined that was more than likely his fault. With him out of the picture, those monsters would probably all congratulate the Boss, telling him how they had been waiting for the day that Sans left.

 _And then..._  Sans would go back. He'd pop back up in his Underground, his presence spoiling all of Boss' celebration. He'd ruin everything, like always. Sans would just show back up. And then who could tell what would happen next?

He'd probably just die anyway, as punishment. For all Sans knew, these were the last few hours of his life, and he was spending them alone, in the lab he had hoped to never return to again in his life.

 _Don't you fucking cry again._ Sans scolded himself mentally as the red tears threatened to spill from his eye sockets once more.  _Dammit._ Could he not hold it together for more than two minutes? Could he stop being so weak for once?

Of course he had gone and had another one of his meltdowns here. Of course he couldn't just have these monsters send him back to his own universe without making a damn scene. Sans hated having other monsters see him in such a sad state. Like the monsters in his universe didn't already know he was weak enough. If the rest of the Royal Guard knew about Sans' breakdowns...

But it hadn't been them who had gotten the fine pleasure to witness one of Sans' panic attacks. Rather, it was the Undyne and Boss of this universe, and somehow that made it so much worse. The skeleton had seen the heart-wrenching looks the two had given him as he sat, sobbing like the pathetic mess he was.

He hated it. Hated their kindness, their pity, how they even went as far as to try and comfort him after the whole experience. Why? Why couldn't they just leave him alone? Why couldn't they just let it go? None of it mattered anyway. The machine to send him back home was still looming over him, and it wasn't like they had built the whole thing for no reason. They needed to rescue  _their_  Sans. The one that actually meant something to them. A single hallucination and a bit of crying on his part wasn't going to change that fact.

Why couldn't these monsters be mean? Why couldn't they be assholes like everyone else in his life? Why did they have to make this whole thing so much more painful for Sans? It was so much harder for the skeleton to go back to his Underground knowing what could have been. What  _was,_  for some incarnations of himself.

 _Why can't they just be terrible so I can just hate them?_ Instead they had to be these nice and caring goody two-shoes. If only he could despise these monsters like he did with the other monsters in his Underground. That would've been so much easier. It would've all been so much simpler. Instead, rather than let Sans hate them after they tried to take his soul- no, not take, ask for, because the monsters of this place were just too nice for something like that- they had instead apologized. The other Papyrus hadn't even known that Sans would react the way he did. He had never even considered it.

It was infuriating, because try as he might, it was just like his situation with Boss. No matter how he tried to spin it in his mind, no matter how many times the scene replayed in his head... he couldn't do it. He couldn't hate them. Even when it meant everything would go smoother.

But things weren't turning out very smooth, because only feet away from him, on the other side of thin wall in as just as poorly lit of a setting as the one Sans was sitting in, the Undyne and Boss of this universe were busy debating what exactly they were going to do with him.

 _Just send me back._  He didn't really care anymore. He honestly couldn't see why he had ever thought there was even a chance of him staying in this place. Why had he even bothered to hope at all, when he always knew that hope would lead to disappointment- to hurt. The ever familiar, always persistent feeling of hurt.  _Let's just get this over with._

Maybe he'd be lucky. Maybe Boss wouldn't kill him. Sans could see a few possibilities where things might turn out alright. Alright being him not turning into a pile of dust at the end of this day. The Boss would punish him no matter what. Beatings were commonplace for his usual shows of disobedience and incompetence. But running away, as Boss would undoubtedly assume he had done... that went beyond the normal rebellious acts and failures that Sans was regularly punished for. That would require something much worse... if not death.

Maybe Boss would tear out his bones. Some sort of amputation- actually... no. Boss would probably leave his arms or legs alone. Without those, he'd be even more useless to the larger skeleton. If anything, Boss would carve out his ribs. Those served no purpose to the stronger monster. They only protected Sans' soul, and the Boss hardly cared about that. He'd rip them out one by one, with his gloved hands. Possibly even leave a few of them only half broken off, so Sans would have to finish the task off himself.

The bones would grow back, eventually. His magic would heal them as spare reserves leeched off from his soul, repairing the broken bones. Unfortunately, extra energy like that was something the skeleton didn't have in bulk. Or at all. The Boss barely paid him enough to have a meal a day. More likely than not, the bones would never fully grow back, always lacking the magic they needed to heal completely.

But that was only if Sans was lucky, and if Boss didn't decide to just kill him on the spot when he returned. Which he more than likely would.

 _I'm leading myself on again._ Sans realized. His thoughts had jumped from one thing to another, until they had finally returned to trying to inspire hope in the skeleton's mind. Hope that maybe this day wouldn't be his last.

 _Hope only leads to disappointment._ He should just accept the fact that he was almost certainly going to die when he got to his universe. It was better to disperse his false hopes now than to let them gather. If he did that, that hope would only be struck down as one of Boss' magic attacks pierced his soul, shattering it into a million pieces and finally breaking his fragile 1 HP life.

It was better to just accept the fact that his life was over. That this was the end for him.

 _This is it for me._  For some reason, Sans thought that the realization would stir up something in him. Fear, panic, sadness, anger or just... anything at all. Some sort of emotion that the skeleton would be able to feel. But there was nothing. Nothing at all.

His natural sense of self-preservation had long since been overwritten. Living for years where your only purpose was to fulfill the needs of an abusive, uncaring master tends to do that. And Sans hated himself so much that he could hardly care about what happened to him at all.

There was no feeling. No emotion. Just emptiness. He was probably going to die, and he could hardly even bring himself to care.

_Let's just get this over with._

* * *

The flowers were new.

They seemed to just start popping up out of nowhere. One or two pots of them in a hall every now and then, placed randomly by the side of closed doors. Their vibrant gold petals were such a stark contrast to the dark blue corridors, even despite the fact that the plants themselves were either dead or wilting.

They were nice. Not just because they were something different for a change in the depressing dark halls of the underground lab, but because they assured Sans that he wasn't getting lost. The skeleton had no idea how long he had been traversing the basement of the lab before he came across the potted plants, but he knew they were a good sign. Seeing something new like them meant he wasn't just going around in circles and that he was actually getting somewhere- that somewhere hopefully being the exit he was searching for.

But then the plant life became more and more prominent. Suddenly there was more and more of the flowers, lining the floors of the halls in dusty old pots. The empty corridors from before were instead replaced with hallways where pots and pots of the flowers sat, seemingly forgotten without any light or water to survive.

It was odd. Sans didn't understand why the same crazed scientist who was involved with testing monsters' reactions to pain and Determination also saw it fit to horde such an excessive amount of the same yellow flower in the lab. But what Sans did know was that whatever the reason may be, it wouldn't mean any difference to him or his escape attempt whether he held that knowledge or not, so the skeleton just kept on going.

 _Maybe she tests things other than melting monsters and killing them._  Maybe the doctor had a second side to her- one that was a bit less psycho- that just enjoyed working with plants. Perhaps she tested them for something. Sans knew that the Undyne back in his Underground loved to work on many projects at once.

Sans kept on limping forward, through the halls. The flowers were nice, but not as nice as an exit. The skeleton knew he needed to keep his priorities in check. Escape and survival first, stop to smell the flowers later- when he was sure he was going to be safe.

He turned right at a bend in the corridor where the pathway changed directions. There were still more flowers, and in the few feet the skeleton could manage to make out in the poorly lit setting, it seemed just like every other hall. It took him a second before he registered the light at the end of the hall.

 _An exit?_  Sans thought eagerly. The skeleton feet began to rise and fall faster than before- the urge to escape driving them forward. His slow, weak stride broke out into quicker stumble. It was hardly the same speed as a standard walk, never mind a run, but it took all of Sans effort to keep the pace up. As he maneuvered his weakened limbs forward, the same yellow flowers grew more and more in number beside him, until the side of the entire hall was packed with them.

 _It's not an exit._  Sans recognized the fact as he began to near the end of the hallway. It was just some sort of room- one with light in it for a change. Sans' pace quickly slowed, returning back to the pace that he had set for himself before. It wasn't the escape route the monster had been hoping for, but despite the initial disappointment that realization brought, Sans couldn't help but feel something spark inside his soul. He was finally getting somewhere other than the same dusty old corridors.  _It's... it's..._

 _It's a nursery?_ Indeed, as the skeleton's steps brought him into the first room with light he had seen in hours, he learned that the room was indeed some sort of nursery for the same yellow flowers that filled the hallways in bulk.

 _I wasn't expecting that._  He admitted, allowing himself a moment of rest to take the room in. In all honesty, the skeleton wasn't sure what he had been expecting- but a plant nursery definitely hadn't been it. Sans had more or less been preparing himself for something twisted and evil, like seemingly everything else in the distortion of his own reality. Something along the lines of the graveyard of monster remains in Waterfall, or the dozens of rooms in this same lab that this universe's Royal Scientist used to capture and hold unwilling test subjects such as himself. He had been more than ready for this room of the lab to hold something just as terrible.

 _But..._  it didn't. The room was filled solely of dozens of plants, sitting up on a counter under the light source that hung from the ceiling above them. There were no painful experiments or tools to conduct said tests. There were no piles of monster dust. Just plants. Not even evil plants. Just plants. Flowers, that just sat there, doing absolutely nothing.

Oddly enough... it felt kind of nice. To see something so  _normal_. Something in this universe that wasn't affected by the change that seemed to alter everything else. The flowers weren't twisted versions of the flowers in Sans' Underground. They didn't try to kill Sans. They didn't try to rape him. They didn't inject his soul with dangerous substance. They didn't chase after him. They just sat there in their pots, being flowers. Just like they would in Sans’ own Underground.

It filled the skeleton with the same feeling from before- the feeling that had swept over him when he had gained the willpower to make his way out of this lab- when the Determination had kicked in. Except it was just a bit different. The feeling that swept over the skeleton this time was warm and fuzzy. For just a moment, it was all the skeleton could focus on as the warmness spread through his whole body, dulling the pains and aches that his bones still felt.

And then suddenly that fuzzy feeling in his soul was gone. As soon as the comforting feeling had appeared, it had disappeared completely, and Sans found himself dumbly standing in the middle of the room.

 _Time to keep going._  One normalcy in this universe didn't change the fact that he needed to get out of this lab as soon as he could. He was still in a very real danger that he would never have to face in his universe. His life was still at great risk. The skeleton turned, ready to make his way out, when his eye quickly caught on something else in the room.

 _A mirror._  A bit of a strange thing to have in a nursery, but whatever. His need to leave was quickly forgotten as the skeleton caught sight of the glass.

In the mirror stood a skeleton the same height as himself. The body of the monster in the mirror was covered with only the same green shirt that Sans had woken up in. Their legs looked wobbly, and their hand was still bruised from the pounding on the metal door when Sans had been so desperate to get into the lab in the first place. The skeleton in the mirror had a serious expression. There was no smile or frown. Their starry blue eyes looked distant and just a bit less bright. And then... and then there was their skull.

Just a Sans brought his hand up to meet the devastated region, the skeleton in the mirror did the same, mimicking the movement.  Sans winced as his hand traced the unprotected area of his head, just as the skeleton in the mirror did the same. Nearly the entire back of his skull had been crushed by a single hammer blow. Cracks and holes riddled it.

 _Oh shit._  Sans couldn't stop the swear word from slipping out in his mind. He hadn't imagined that it was as bad as it was. His skull was utterly decimated. How was he even alive? Determination or no, that didn't change the fact that his skull was destroyed beyond all repair.

 _How can I not feel all that?_ Sans was shocked. There was some pain from his skull, yes, but there was pain all over. He hadn't believed that the hammer blow had left him in as bad of a state that he really was in. He needed to patch that up pronto. Otherwise, it would take forever to heal back.

The skeleton's feet moved forward, ready to exit the room through the exit opposite of the one he had came from, yet he was unable to tear his eyes of the monster in the mirror. Completely incapable of looking away from himself. From his reflection.

 _That's right._ That was how mirrors work. Sans felt real stupid having to remind himself that. It just seemed so...  _not_ him. The reflection of himself seemed to be of some other skeleton who shared Sans’ basic features, but was not Sans himself. The short skeleton could hardly recognize himself.

 _Is that really me?_  Sans leaned in closer, inches away from the glass. He brought his hand to his face, gently grazing it.  _Do I really look like that?_

Sans didn't know what he had expected. When he saw the mirror, had he been ready to see the face of his regular cheery self? Was he ready for that same ridiculous, over the top smile that greeted him every morning in the mirror of his own home, in his Underground? Was he expecting the blue eyes that shone like nightlights, bright as the stars, full of exuberance and excitement?

Or was he waiting for the same image he had seen in the reflection of the frozen pond this morning? Sad eyes busy forming teardrops, with a frown that was incapable of turning itself upside down. Was Sans expecting that image? The broken, unsure picture of himself, that couldn't handle problems? Or the happy-go-lucky him that didn't have to?

 _I didn't know I could do this. That I could **be**  this. _A confident, serious Sans. Not occupied with being happy or sad. Not focusing on his emotions or his hurt. Not paying attention to his childish fears of the dark or being left alone. A Sans too busy just trying to stay alive to get caught up in all those little things. A Sans capable of handling himself even in the worst situations, with a broken skull and mangled soul.

He could have never even imagined himself being like that. In a way, it reminded him of Alphys- the one in his universe. The one who was the Captain of the Royal Guard, who was strong and powerful, always doing what was right and just, fighting for the future of the monsters of the Underground. The monster that Sans, like so many others, always looked up to.

Before today, Sans couldn't have saw himself as anything besides the energetic cheery skeleton who was a master chief and soon to be member of the Royal Guard. He couldn't have imagined himself as anything other than that because  _that_  was him. That was the very definition of who he was. An excited ball of energy with an infectious happiness.

But here he was. Standing in a dark lab, universes away from home. Ready and capable and serious. Wasn't that a strange idea? Wasn't that so different from what he had always been?

 _Which one am I really?_  Was he the Sans full with cheery happiness, or the one tearing up in sadness? Or was he the one who remained confident in the face of danger?  _Is it even possible for me to be all three?_ They were all so different- it was almost as if they were polar opposites of each other. _Can I really be all that?_

Sans leaned closer in to the mirror, his blue eyes searching deep into their reflection for some sort of answer to his question. _Can… can this really be me?_ He felt so unsure. It… it couldn’t possibly be him, right? Was this just some other side of him that he had never had to see before? Some part of him that he had never had to call on for help?

_Is this really me?_

_*WHOOSH!*_

The skeleton jolted out of his trance as what sounded like a fan kicked on.

 _Crap._  So much for being capable. How long had he just spaced out for? What happened to being focused?  _I've got to find an exit._  Quickly, Sans pulled away from the mirror, moving his feet once more to the beat of the Determination filled soul in his chest.

Just like the flowers, the fan and the lights in this room were also a good sign. Those things meant that there was a source of power somewhere nearby. A source of power meant the elevator he'd come down here in had to be close as well. At least, Sans had assumed it had been an elevator in which he came down here in. The skeleton had only seen the control panel before blacking out.

Which meant that he was getting closer.

* * *

"We can't do this," The words fell softly from the Royal scientist's lips, Undyne afraid what the other monster's response might be. "We just can't send him back Papyrus." The larger skeleton only fiddled idly with the string on his hoodie, incapable of finding the right words to respond with. "We  _both_  saw that. You and I both witnessed that whole thing."

Undyne was right. The image was still burned in the back of his mind- the curled up sobbing skeleton currently residing in the room next to them. The same skeleton that looked just like his Sans- like his brother. The same skeleton who  _was_ his brother.  _So much for not getting involved._ Papyrus thought bitterly to himself. That plan seemed to have just been thrown out the window. 

"That's... that's not something we can just pretend didn't happen. I know... I know that that's something I can't ignore." The scientist ran her hand up the sleeve of her lab coat, scratching her scaly skin awkwardly. "And... and I know it's not something you can ignore."

 _She's right._  It hurt Papyrus just imagining the shit that version of his brother had to have been through to break down like that. How could he just send his brother, any version of him at all, back to a universe that caused that much hurt willingly? How could he possibly live with himself knowing he sent this poor monster back to a life of abuse?

But at the same time... it was some sort of double standard. Because every moment that skeleton sat in that room in this universe meant another where Papyrus' Sans was stuck in the same hellhole that caused him to turn out like... that.

As much as the image of the crushed, destroyed Sans he had just seen disturbed him, even the mere thought of his bro in that same situation was a hundred times worse.

"It's not like we have much of a choice," Papyrus answered weakly, hating himself for saying what he did.  _I really am terrible, aren't I?_  That didn't matter though. Papyrus would never choose the Sans he had just met over his brother that he'd cared, loved, and raised for years. "We can't just... abandon _our_ Sans like that."

Undyne sighed, acknowledging the clear reasoning behind the skeleton's statement. "I know... I know..." If they really did have to make a choice, the decision was obvious even for her. The Sans scrunched up on the floor of her lab was a heart-breaking sight, yes. Undyne could scarcely imagine what had run through the skeleton's mind in the last few minutes since the incident, never mind during. She had seen the fear in his eyes when Papyrus had gotten closer to him. The wild, desperate panic in his eyes that evolved into the struggle that ensued to free himself of the larger skeleton's admittedly light grasp.

All that was awful, yes, and the Royal Scientist couldn't help but let the tale pull at her heart strings. But at the end of the day, the idea of her friend- of the Sans from her universe- having to be put through such horrid circumstances that had shaped this other Sans into what he became was even scarier. Undyne didn't want to imagine that sweet, childish, friend of hers having to go through any sort of abuse or mistreatment.

"But..." There was an idea sparking in the scientist's head, just beginning to take root in her mind. "But what if we didn't have to choose?"

"Huh?" The skeleton turned back to Undyne was a skeptical look on his face. "What do you mean?"

"Well..." Undyne clenched her wrist tight as she felt the other monster's gaze burn into her. He was so unnerving when he was serious. No, unnerving wasn't the word for it- more like utterly terrifying, a completely different version of his regular, relaxed self. "What if rather than swap the two Sans-es... we tried to pull back ours from the other universe?"

Papyrus' eyes began to narrow and his jaw parted, ready to speak, but Undyne felt the need to explain herself before he did so. "We could build another machine... probably even reuse a whole lot of the parts. There would be a few major changes to the mechanisms and the magic... but still, we could do it!"

Papyrus mouth still hung wide, ready for the skeleton to get the chance to talk, but Undyne was still going strong. "Of course, the universal repercussions would be a whole other problem completely. Having two of the same monster in our universe... who knows what could happen? Something like that's never occurred before... it's completely impossible to tell what would occur. And whatever universe we pull our Sans from will be left with none. That could utterly upset the stability of them... or do nothing at all."

Undyne knew she was getting ahead of herself, but she could just see the idea so clearly in front of her. They could save this poor soul, and their own Sans too. They could do the  _right_  thing here. They didn't have to make a choice between two lives. They could give this version of her friend happiness. Give him safety. The one thing he thought he would never have.

They could do it. With just a few hundred pounds of a hammer on metal parts and the wielding of a new base for another machine, some more circuits, another computer to monitor the progress, and some more magic to provide for their new purpose, something like that was possible. That was the magic of science. That was the magic of magic  _and_  science, working together, they could accomplish great things. They could change the lives of monsters for the better.

"I... I think it could really work!" Undyne could feel the excitement in her voice at the very idea. Her machines, her inventions, changing the life of this abused monster for the better. That was a whole lot more than she could say about all the countless minor projects she'd done in her time as Royal Scientist, of which none seemed to do very much to improve any monster's life at any scale as large as this.

"How long?" Papyrus said the words just a bit too quietly for the scientist.

"...huh?" Undyne had pretty much tuned the other monster out, preferring to get lost in her own thoughts.

"How long?" The skeleton repeated the question.

Undyne swallowed and thought for a moment. Taking into account the possibility of a universal disruption that could upset the balance of the multiverse, that meant they'd have to make some necessary preparations for that chance. But they could probably save a whole lot of time not bother to make a second machine and instead reworking their existing one. It would take Papyrus a few hours to infuse magic into it, meanwhile, that would give Undyne some time to start replacing some of the parts... completely replacing them, with new circuits and everything. They'd have to rethink the entire design and everything. In fact, the machine would be serving a completely different function than the first model.

"A... a few weeks. Maybe one or two. Four or five at most," Undyne estimated. It was a generous estimation, to say the least. "We can cut some corners and maybe have it done in a few days." That had been the case with the machine they'd made today, but then again, that had yet to even know  _if_  that machine could work. If that machine did turn out to be a success, than that would mean the two of them would've discovered a way to manipulate the multiverse. That would allow them to build this second machine in much less time.

And then again, if there were some unforeseen difficulties sitting in their way... that number could be much, much larger. "Possibly... possibly even a few months... to a year." It was just like the machine they had made today. A rushed design to make an undependable, flawed model that risked a lot that you otherwise would not have to with a slow, well understood plan. The time frame varied so wildly that it was impossible to predict at all.

"That's what I thought," Papyrus' shoulders fell back as he sighed, the stress of the situation clearly getting to him but the skeleton unwillingly to admit it. "We don't have a few months. We might not even have a few days. Or minutes."  _Who knew what's going on in whatever universe my Sans is stuck in?_

"So... we send him back now,"  _Or at least we try to._  "With the machine we've already made. We swap his place with Sans'. Then we make another machine. That means we have a bit more time to work on a machine to pull him back, right?" After all, this other Sans had somehow managed to survive in his messed up universe for all his life. He could certainly last a few more months.

"Maybe, but..." Papyrus could feel all his thoughts cram packed in his head, fighting for his attention. His worries about his bro, concerns about getting involved, about the machine actually working in the first place- all of it, swirling around in his mind giving him one massive headache. If this were any other day, that would've just given the skeleton a reason for a quick nap. But today was far from any other day. "It seems dangerous. Playing around with universes like that..."

"The chances of it actually throwing off our universe seem minimal,' Undyne argued. "I only mentioned it because it is  _possible_. Just not very. After all, this whole thing involved a switch across them, and everything seems fine right now at least."

"Why is it that we aren't just focusing on  _my_ Sans?" Papyrus knew he sounded a bit possessive with his wording, but he could hardly bring himself to care to correct it. "You seem awfully concerned about this other version of him."

"Because we should be!" The words slipped out a little louder than Undyne meant them to. "And frankly, I don't see how you aren't!"

"I am," Papyrus admitted. "But that doesn't mean we have to do something about it."

"I don't even get how you can say something like that," The Royal Scientist was appalled with the larger skeleton. "I've told you, this isn't something that we can just ignore!"

"You just don't see it, do you?" Papyrus looked at the scientist with cold, unapologetic eyes that sent shivers down the fish's spine. The look froze Undyne in her tracks.

"See what?" Confusion was evident in the scientist's voice.

"There are millions upon millions of universes out there, right? An infinite number, beyond our wildest imaginations."

"...Yeah, so?" Undyne was familiar with the theory of the multiverse- well, technically, that was no longer just a theory anymore. There was living, breathing proof sitting in the room behind them.

"Out of all those universes... how many do you think are like his? How many Sans just like him exist?"

"What are you talking about?" She didn't see how any of this related to their discussion.

"Just answer the question." Papyrus didn't even acknowledge her inquiry.

"I'd say there's probably... a very good number. When we're talking at a scale of unlimited possibilities, that would mean there'd have to be a universe like his own with every single combination of different choices. Meaning that there very well might be an infinite number of his own type of universe, which is just one specific group of possibilities in the multiverse."

"Exactly."

"Exactly what?" Undyne wasn't seeing how Papyrus' point was supposed to come full circle.

"If there an infinite number of those Sans out there... each one abused, tortured and... broken, just like him... then what difference does saving just one of them make? Does it not only just complicate things, while an infinite number of the same monster is left abandoned in all those other universes. Do we not just risk the stability of our universe for what in arguably meaningless? For something that should mean absolutely  _nothing_  to us at all?"

"Just stop Papyrus," Undyne wasn't about to let him continue rambling over the value of a single life like some philosopher. "You know we can't look at things that way." Taking a viewpoint like the one Papyrus was arguing for was dangerous. It allowed one to distance themselves from everything, using the age old argument of "if our universe in just one out of a limitless amount, what difference do we make?"

"I'm just saying," Papyrus twiddled with his hands, a bit quieter with his words as it slowly dawned on him what it was he had just said. He did realize just how unemphatic he was being. He did see how unfair he was treating this whole ordeal. He did recognize just how much he was starting to sound like  ** _him_** _-_  and no, Papyrus wasn't talking about this other version of Sans- or his own brother. "It just seems like a big risk of the stability of our universe for a reward that doesn't change much at all."

"But it does change something- a whole lot, actually. Just not for us," Undyne turned around to face the doorway behind her, leading back into the room. "Imagine if you were him. What do you think he has to go through, everyday in his universe? If we could save him from that... it would change him and his whole life. It would save him." Papyrus still seemed reluctant. "He's not  _nothing,_ Papyrus. He's a monster, just like you or me. And the stuff he's had to go through is absolutely horrendous. Nobody should have to suffer that sort of torture. Not to mention the fact that this is just the right thing to do. You know it is, Papyrus."

Silence filled the room for a moment before the skeleton finally caved in. "...Yeah."  _She's right, and I know it._  "But... just when do we draw the line? What if we get too involved?"

Undyne understood the other monster's concern all too well. Getting too involved in the messy issue that was this Sans' universe could prove a fatal disaster to all of them. The Royal Scientist saw how they could do it from a scientific perspective, but if they weren't going to handle this situation with the utmost care, this whole thing could end up blowing in their faces. "We'll cross that bridge when we get there... we can just wing it, right?"

That coaxed a small chuckle from the larger skeleton. "And here I thought you were the one against winging things." Papyrus sighed sadly as the chuckle faded. "I guess I'm just a little too concerned about my bro to see things straight." With issues involving his Sans, Papyrus wasn't always capable staying completely level-headed and reasonable. Clearly.

"Oh yeah," Undyne smiled back, unable to resist the urge to tease the skeleton. "You definitely don't melt under the stress like Nice Cream in Hotland."

"Shut up," Papyrus playfully pushed back at the scientist, who got a chuckle from his reaction. The two of them stood in the hallway for a few seconds afterward, a comfortable silence hanging over them.

 _Can't relax just yet._  Papyrus reminded himself.  _I can do that after we get Sans back._  Hopefully, that would be much sooner rather than later. It was a bit harder for him not to slip back into his regular, lazy self without the constant reminder of his missing bro. And the moment he realized he had let himself forget about Sans, even for a minute, the guilt swamped in, attacking him for not being hard at work to restore his brother to him.

And just like that, the lax mood in the corridor broke away, and it was back to all work and no play as Papyrus marched his way back into the other room.

* * *

 _This was really it, wasn't it?_  Sans asked himself as he stared at the object in question. Two metal doors sat across the room, opposite of him, sealed and waiting.  _I found it._ The exit. After what felt like an eternity of searching, he'd found his way out of this lab.

Things really had gotten much easier once the skeleton had found his way out of the labyrinth of corridors and into the connecting rooms. There wasn't as much light in the following rooms as there had been in the nursery, but there had at least been some, enough that Sans could at least see the whole of his surroundings and not just a few feet from his face.

When Sans had left the nursery filled with those yellow flowers and mirrors, he'd ended up walking into another strange room. Strange not in the sense that it was filled with cruel, unusual torture mechanisms, but strange in the sense that the skeleton couldn't see what in the world it was doing in an underground laboratory. The room had been filled with several low lying counters that seemed to be functioning as some sort of beds. Each table had a cheap, crummy mattress above it, with an old, torn sheet as the only blanket, and the pillows were flat and poorly stuffed. Clearly, quality had not been the sole factor that had been taken into consideration when building the furniture pieces. Sans couldn't imagine any monster getting a restful sleep on any of the thrown together beds.

From there the skeleton had struggled to make his way down another hall, instead lined with shut down computer monitors as opposed to doors or flowers. The hall lead to what seemed to the skeleton to be some sort of main lobby to the lab.

The lobby had a few things in it. Of all of them, Sans found the vending machine to be the most intriguing. Just the thought of the food or any sort of subsistence at all was enough to remind the skeleton of the fact that he hadn't eaten since the dinner when he had been back in his universe, and that had been who knows how long ago. All the injuries he had endured since arriving in this Underground were really taking their toll on the energy level of the magic left in his soul. He felt like he was running on empty for the first time in years.

Back in his universe, he ate a three meals a day, never skipping breakfast, lunch, nor dinner. It was important to keep his energy conserved if he was ever to be a member of the Royal Guard. The same was true here, if not more so, but unfortunately, it was a bit harder to keep a regular meal plan going when he was constantly preoccupied with avoiding killers and crazed scientists.

Of course, vending machines required gold, and that was something Sans didn't have. Even if he hadn't spent all his money on the fare from Snowdin to Waterfall, it would't have mattered, seeing how the skeleton had completely lost all of his possessions and clothing when the scientist had knocked him out. Not like the skeleton was going to stick around just with the sole purpose of looking for them. Clothes were replaceable. His life was not.

So Sans had kept walking along, down another hallway that turned right and just seemed to keep going, until reaching a small room that had absolutely nothing in it. Nothing except for one small set of metal doors. Which lead to just one thing.

 _The elevator._ Sans' feet had frozen in place as his blue eyes settled on the shiny doors that marked his ticket out of here. _Could it really be?_ Had Sans found his way out?

Slowly, Sans had made his way to that shiny set of doors, approaching the button with an up arrow on the door frame. The skeleton's weak hands reached out, at a snail's pace, putting pressure on the device. His motions were drawn out and careful, as if he was afraid to be too hasty and accidentally mess something up. 

Admittedly, it felt a bit anticlimactic, simply pressing the up button and waiting casually as the doors parted at his command. It was an odd idea that after so much time searching, after being thrown in a room in the middle of a maze that seemed endless, that the skeleton could just... walk straight out the exit, with absolutely no opposition to him. Not that he was complaining, but Sans had pictured that it would be a bit... harder? Like the exit would be something with a few more barriers around it, like some sort of special security card or key needed to access the elevator. He had imagined there being a bit more standing in the way of his escape, and not just one single set of metal doors that opened whenever the skeleton wished.

The skeleton wasted no more time as he hurriedly limped through the doorway and into the elevator he had spent God knows how long looking for. Installed in the back wall, just like he expected, was a control panel, with just two floor buttons. Sans smashed the button with the label, "GROUND LEVEL," without second thought. And just as he did so, the elevator doors behind him slammed shut, locking him in the metal box as it began to rise.

Sans could feel the floor rising beneath him, gravity pushing down harder on his already unsteady legs. He leaned himself against the walls in the corner of the room for extra support. For a few moments, he waited, silent, still expecting something to go wrong and get in his way.

And at first, nothing did. The elevator didn't surge back downward without warning, or stop completely in the shaft. It just kept going up, bringing Sans back up to the Underground. And it kept doing so. Nothing bad happened to him for a change. The skeleton let out a sigh of relief he didn't know he had been holding in.

 _I made it._  Sans allowed himself a small smile. _Gosh,_   _I finally made it. I did it. I'm gonna be okay._ He had escaped. He had gotten out of that lab.  _And all by myself._ There was a certain sort of pride that came with being independent enough to accomplish things like that alone, and Sans was just starting to discover that. The warm feeling bubbling in his chest was a mixture of that pride and the Determination from before.

 _Okay..._   _so what now?_  Sans needed to find somewhere to go. The monster needed shelter and food. He wasn't going to survive without both of those things. His next step should be making sure he got what he needed. And what he needed was a place to settle down for a little while, at least until he was in  better state than he was now. Sans also needed food for the extra energy to repair his skull and other damaged bone tissue. As for his soul itself... the skeleton wasn't really quite sure.

The Determination didn't seem to be having the negative affects this other Alphys had predicted. At least, not on him. He had yet to start melting. Hopefully, things stayed that way. The pain had gone away too, dulled by the adrenaline and the pure rush the red substance gave him as it coursed through the veins of his soul. Meaning Sans could focus on more pressing issues than the seemingly stable condition of his own altered soul.

 _Food and shelter._ He was sure he'd have no trouble getting both of those things in his Underground. The thing was, this place wasn't his universe. It was nothing even close to it. Kindness and compassion were feelings Sans hadn't seen from the other monsters here, which was a deeply disturbing thought in itself. But that also meant they'd all be less willing to help a injured monster such as himself out.

 _What about the Capital?_  Papy and he had grown up along the outskirts of the city. Sans might be able to survive on his own out there. He knew a thing or two about making camp. He'd set up many times for the two of them when he'd been younger. Getting food would definitely be a bit harder, however. And the monster of this Underground's Capital would probably not be too supportive of a foreign monster begging them for scraps.

 _Waterfall is a definite no._  That wasn't even a choice. He'd hardly be safe there, with some crazy serial killer on the loose.

Which left Hotland, Snowdin, and the Ruins, which was probably just as inaccessible in this Underground as in his own. So just Hotland and Snowdin. A choice between returning to the town of the murderous version of Papyrus or staying where this mad scientist would have the least difficulty finding him. Not exactly the best option- all Sans could choose from was the lesser of two evils, yet both of them were equally disheartening options.

 _Maybe I can convince the Innkeeper to let me stay a night._  He had no money to pay. Sans knew the innkeeper in his universe would allow him to stay without having to pay with no questions asked if she saw him in his situation. She was always awfully nice to him. Obviously, that would be a bit harder of a goal to accomplish in this colder, crueler Underground, but hopefully there could still be some way Sans could manage to convince her.

 _But..._ That meant Sans had to find his way  _back_  to Snowdin. He couldn't pay the fare for a ride with the River Person. That meant he'd have to cross Waterfall on foot, where the same killer was probably waiting for him. Which was also not a very good option.

 _There's got to be some other way-_  The skeleton's thoughts were interrupted by one loud ding, as the elevator stopped where it was. The doors parted their way for Sans, allowing the skeleton to see the  bright white tile of the main floor of the lab. 

 _Finally._ The skeleton pushed off from the wall he had been leaning on, limping towards the exit. However, just as he had begun to do so, a familiar clicking against the white tile of the lab sounded, and jolted Sans out of his relief, freezing him in his tracks. The noise had almost ingrained itself in Sans' mind with the feelings of hurt, panic, and fear that it brought. Sure enough, just hearing the footsteps was enough for a wave of anxiety to wash over the skeleton.

 _She's here._  Of course she was. Why hadn't Sans recognized that as being a possibility? Why hadn't he prepared- or been ready- or done anything at all? Her footsteps were getting louder with each step, coming closer to the right side of the elevator.  _Oh no._

In a blind panic, Sans swung his head around, scanning the elevator he was in. The empty space of the area provided him with nothing he could use to his advantage. The only thing he had in his power was the control panel, and even that only seemed to go back down to the floor Sans had just tried so hard to escape from. Pressing it would only be delaying the scientist from getting to him, as she would undoubtedly follow the skeleton back down to the bottom floor, and this was the only exit available to him.

The sound was real close now, and the anxiety in Sans' soul told him that delaying whatever might happen next was much better than having to go through it now. Without another thought, the skeleton crushed the, "BOTTOM LEVEL," button with his bare hands. Quickly the doors began to force themselves closed, but not before the head of a small metal tool found its way lodged between them.

And for the first and probably only time in his life, Sans wanted to curse the safety features of an elevator with every rude and ill-mannered word he knew. Because thanks to the stupid tool being stuck in the way of the doors closing, the elevator actually thought the body part of some monster was stuck instead, and the doors automatically began to part.

Sans' hand and fingers pounded on the close door button so fiercely, over and over again, that he was sure he was about to destroy the mechanism entirely. Yet none of that mattered, because the crazy scientist was already making her way into the elevator with Sans.

The psycho smirk of Alphys' face was so chilling that Sans could feel shocks running down his spine, the fear paralyzing him completely. The hammer in her gloved hands looked so familiar to the skeleton, probably because his skull had already become intimate with the tool once today.

And just then, the elevator decided it was a perfect time to shut its exit, leaving the two monsters trapped in the metal box together with nowhere to go. Shiny metal doors sealed themselves tight, closing off the only way back to the top floor of the lab and Sans' escape, snatching away the skeleton's last chance at freedom. The scientist spoke no words as she slowly raised the tool that had already killed Sans once over her head, an expression of pure evil over her face.

And in turn, the only thing Sans could do to protect himself was to shut his eyes tight as the first swing came down.


	11. Announcement

Hey.

So...

It's been awhile.

Then again, I guess eight month with little more than a peep is a bit more than "awhile." And seeing as how you are probably well aware of how short this chapter is, as well as how these author's notes consist of its entirety, you are probably well aware of where this is going. If you were excited for an update after all this time... I really hate to disappoint those of you who've stuck by this story, waiting for a new chapter after I've strung you along for nearly a year now.

Because as of writing this, "The Tale of Two Timelines" is officially dead.

Maybe that's a little bit dramatic, but I'm sorry to everybody whose held onto hope for the last eight months. Typically, I don't like to announce the death of any of my stories after such a long hiatus. Announcing this after almost a year of teasing you guys about an update doesn't quite sit right with me. Which is why almost all my other "dead" fics have never been officially declared such. But TToTT is an exception. I feel like at least owe you all some explanation- especially to those who've stuck it out throughout this indefinite "hiatus" and encouraged me to plow onward, enjoying my writing despite its many flaws.

Let me get one thing clear, right off the bat; I don't regret starting this story. Even if a part of me knew that I would never finish it, and that I had bitten off far more than I could chew, I enjoyed every minute of it while it lasted. You guys here on AO3 are seriously amazing. I've received so much positivity and encouragement with TToTT. And beyond that I've received advice and constructive criticism that is  _actually_ constructive. I love writing stories for everyone on here- not just because I'm proud of seeing others enjoy what I create, but because it's exciting to become a better writer while doing so.

Okay, now I  _know_ I'm being a touch too dramatic. Not to mention off-topic.

You see, this story started off without too much forward thinking on my part. As it grew, and more and more people started to take a liking to it, I tried to throw more and more ideas in to compensate for a lack of a solid plan for the story's plot. I wanted to add so much to the fic that it eventually became a very long and drawn out thing. Heck, it's ten chapters long, with over 100,000 words, and the story is still in what I would consider to be the "introduction" phase.

I had a lot planned for TToTT, which is why it pains me so much to see it die. Over the last four months, I've tried to rewrite the story from the beginning. I've desperately attempted to save the story by restructuring it and smoothing out all the flaws and low points that have bugged me, but that just made the story bulkier and more troubling to deal with. The process of rewriting ended up just as the process of writing had: starting strong, but slowly sputtering out and dying towards the end. 

I can't drive myself to continue this story any longer because it's just _too much_. And I don't mean that in any melodramatic way- TToTT is literally too much. Too many words, too many half-baked ideas, too much filler, and of course,  _too long._

If I'm walking away from this story now, after straining myself so long in the futile attempt to reign it in, I have at least learned a lesson from this. A well-known, if not cliché, lesson in writing:  _more is less._

TToTT is messy to deal with. I'm well aware that it's slow. Lately, I've been reading a lot, and that has helped me identify just how  _unnecessarily_ slow it is. I mean, after all, 100,000 words is  _way_ too long of a build up for a story like this. Especially since a lot of books are less than that length.

I've realized that I need to work on a smaller scale than this. I'm actually quite eager to do a number of oneshots that this story has been preventing me from concentrating on. And in truth, I've been starting to think that a lot of the concepts I've had for TToTT would fit better in short, one-off works.

I know many of you might be disappointed by this, and I apologize. Especially to everyone who I've reassured that the story will continue after the first 10 chapters were rewritten. I'm really sorry to all of you who've been looking forward to an update for so long, but I've decided I want to move on to write other stories- nothing quite as long or built up as the TToTT. 

Thanks for all your support and encouragement over this last year,

Reader010~

**Notes for the Chapter:**

> Two days later, and I've got a quick update for you all.
> 
> Axing this story after so long was hard. Seeing so much potential lost after months of buildup and hours of work hurts, but at the same time, it's utterly relieving. I shot way too far with this fic and I've needed to let it go for quite some time now.
> 
> A lot of you guys have been super understanding in the comments, and I can't express how grateful I am for that. The little hate I have received has been drowned out by your encouragement. So many new faces have reached out to assure me that it's alright to move on. I can't thank those of you enough; I want to dedicate myself to other projects, and seeing so much support makes me eager to do so.
> 
> Seriously, you guys are awesome. 
> 
> Signing off for real this time~


End file.
